Airports and cities in the context of globalization: a multidimensional symbiosis in the Adolfo Suárez-Madrid Barajas Airport The interpretation of airports as places where landings and take-offs occur is obsolete. Globalization, the ‘mobility era’ and a so-called ‘culture-cognitive capitalism’, favour the reconceptualization of airports and may turn them into necessary infrastructures for every city that aspires to be ‘global’. An airport-city symbiosis is analyzed and is defined from a multidimensional perspective (operative, economic and symbolic). These perspectives have led to important works of expansion and renovation of airport facilities and a multiplication of the services that may be developed within them. The results show this multidimensional symbiosis in general, although it is analyzed in detail for the Spanish case study of the Adolfo Suarez-Madrid Barajas Airport, which is the main air gateway of Spain to the rest of the world and the most important European hub connecting Latin America with Europe. Its global exposure is reflected in its ability to stimulate the economic and residential development of its surroundings and to strengthen the modern image of Madrid, thanks to morphological changes and increases in non-aeronautical uses, which are viewed as city marketing initiatives that help to promote Madrid in the world urban hierarchy. KEYWORDS: Madrid-Barajas Airport, airport-city symbiosis, air connectivity, knowledge economy, city marketing, non-aeronautical uses. Introduction Relations between transport-communication networks and settlement systems are a classic subject in geographical studies precisely because not only are they the essence of territorial organization, but also both aspects provide feedback and are mutually supportive (Brotchie et al. 1991; Rodrigue et al. 2013). A special case is air transport due to its importance on the world scale. Although this first statement may seem exaggerated, it is difficult to imagine a world today without airports in a transport system which has contributed to creating global relationships and providing accessibility at increasing levels of movement (Forsyth et al. 2002; Kane 2003). This situation undoubtedly has a profound impact on the scale of the organization of the world (Gago 2003; Dicken 2007), affecting the reformulation of spatial concepts such as mobility, accessibility and distance (Graham 1995; Forsyth et al. 2002). Although air travel has not abolished the latter, it has drastically reduced the time of travel to create a perception and appearance of a shrinking world that is understood in terms of ‘space- temporal convergence’ (Janelle 1969), ‘space-temporal compression’ (Harvey 1983) and the ‘plasticity of space’ (Forer 1978). According to these ideas, distances are reduced and space is contracted, which constantly changes the relative location of places. However, while these effects do not all achieve the same dimension, they are more evident in some airports located in the great cities of the world. At present, it could be maintained that it is almost impossible to configure a large city without a large airport with a geographically varied and intense connectivity, while a large airport needs a city that provides passengers, cargo and therefore economic viability1. This means that there is a strong interrelation between airports and cities, which indicates a need to analyze this necessary symbiosis (Díez-Pisonero 2015). However, this airport-city symbiosis is not just about transport networks, but about places, economic development and place making, among other things, which acquire a considerable interest in the context of globalization, the ‘mobility era’ and so-called ‘culture-cognitive capitalism’. This broader perspective favours the reconceptualization of these infrastructures and calls into question their traditional conception as ‘non- 1It is known that the installation of airports is not always due to reasons of economic profitability; however, in the case of large airports in the world, this has become one of the key parameters in assessing their activity (Gagoet al. 2013). places’ (Auge, 1993); rather, they are places in and of themselves, as well as co- producers of place with cities. This airport-city symbiosis may be analyzed from three different perspectives: (i) from an operational perspective (air hub) since the airport is capable of embodying the varied and intense air connectivity required by any city that aspires to be integrated with world trends (Derudder and Witlox 2008); (ii) from an economic perspective (economic hub), since airports not only generate socio-economic dynamism but also attract new commercial, industrial and recreational uses in their surroundings, which makes them one of the main centres of urban development at present (Cidell 2014); and (iii) from a more intangible perspective (symbolic hub), since airports may be used as a city marketing strategy that helps project the image of the city into the recent cultural dynamics that are defined within cultural-cognitive capitalism (Scott 2008; 2014). The objective proposed of this paper is accordingly to analyze the city-airport symbiosis from these three perspectives, first in general and then in the Spanish case study of the Adolfo Suarez-Madrid Barajas Airport (ASMB), which is the main air gateway of Spain to the rest of the world and the most important European hub connecting Latin America with Europe. The significant work on the expansion and renovation of this facility, the multiplication of new services and activities that are being developing in its surroundings, and its perception as a new landmark in the urban landscape of Madrid are the main reasons that justify its selection as a case study. Methodologically, the city-airport symbiosis from the operative and the economic perspectives is analyzed using a quantitative methodology based on analysis of data from national and international statistical sources. International passenger data from ACI (2015) and the international air connections and frequencies from OAG- International (2015) provide the necessary data to evaluate the international scope of airports; and SABI business and company database, the business directory of the Community of Madrid, provides information on the business headquarters present in Madrid in different time periods. Companies linked to the knowledge sector according to OECD (1996) are spatially represented through a GIS to show their spatial distribution, and to assess the attraction that the airport exerts on the location of this type of company along road corridors leading to the airport, and in territorial sectors between these road corridors. To analyze the city-airport symbiosis from the symbolic perspective, a qualitative methodology is carried out based on 150 surveys completed by airport passengers during June and July 2016, that allow an assessment of the role of Barajas in defining the urban image and identity of Madrid. In total, the survey involved eleven questions grouped into three categories (see Supporting Information). The paper is divided into four parts. After this introduction, the paper focuses on a general discussion about airports and cities from the three perspectives considered, leading to a focus on the Adolfo Suarez-Madrid Barajas Airport in the third section. Finally, the article ends with conclusions drawn from the analysis. Airports and cities: a necessary but changing symbiosis Despite the lack of consensus on what constitutes a ‘hub’ (Button 2002), this type of location tends to be at the centre of ongoing academic research (Bowen and Cidell 2011; Rodriguez-Denizet al. 2013, Grosche and Kophaus 2015). An ‘airport hub’ is an integrated air transport exchanger that concentrates and centralizes much of the air traffic to perform arrival and departure functions from different origins and destinations (spokes) for redistribution; and that channels and redirects to/from other hubs and spokes (Anton 1992) to optimize resources, time and money. Generally, these airport hubs organize and provide the backbone of world airspace by centralizing much of the international air activity, especially following the many changes caused by the liberalization of air transport where strong rivalry has forced airports to become more competitive and more integrated into world networks (Cidell 2006; Derudder and Witlox 2008; Veldhuis 2013). These competitive airports are a reflection of the ‘hub- and-spoke’ system that has appeared, albeit not without problems, in the world air transport network over recent decades; a good example of the changes introduced by air transport is that of the perception of spatial accessibility (Brueckner et al. 2014; Marti et al. 2015). First, from an operational point of view, these airports play a crucial connecting role since their degree of internationalization is very high in terms of the number of international passengers, international seat share or international air connections and frequencies (Table 1). The data in Table 1 show that the main airport hubs are located primarily in Europe. In addition to the liberalization of air transport carried out in this region, the economic dynamism of European cities, their geographical centrality in the global sphere and in some cases their political status as capitals of their respective countries, among other reasons, justify their international weight (Starkie 2012; Zhang et al. 2013). The United States, by contrast, registers a lower presence of international airport hubs at the top of its air traffic system. Although the US has become the leading country in terms of domestic connections, frequency and air passengers (Rodriguez et al. 2013; Richardson et al. 2014), its internationalization degree is decreased due to a large part of the air statistical data being considered national because of the large area of the US2. The displacement of the international economic centre of gravity from West to 2From a methodological point of view, this article uses international data to highlight the world status of airports. However, it is well known that US airports, for example, Atlanta, Miami and Houston airports, also play an important role as hubs since they centralize much of the air activity in the country (Derudder et al. 2007). East means that the Middle East acts as a hinge between Europe, Africa and the Asia- Pacific region, playing a greater role in commercial aviation at a world scale (O’Connell 2006, 2011). This tilting of economic power also benefits many Asian cities since not only do they increase their international status in terms of economic productivity (Taylor 2013), but also their airports act as some of the most important world airport hubs (Ha et al. 2013; Vowles and Mertens 2014). The other world regions and major gateways play a lesser role on the world stage either due to their peripheral position (e.g., Sydney in Oceania) or due to their comparatively lower rate of progress despite their developing character (e.g., Sao Paulo in Latin America and Johannesburg in Sub- Saharan Africa). It should be noted that an international airport hub is not just defined by the large numbers of international passengers, air connections and frequencies it has, but also that these parameters should be distributed geographically in a varied and extensive way. Barcelona, for example, experiences a large volume according to these data, but it cannot be considered an international airport hub, at least not like Madrid, since its connectivity is not distributed as extensively in a geographical sense. Most of Barcelona's international air connections and frequencies are directed to Europe, with limited presence in more remote regions. On the contrary, the connectivity of the Madrid airport is more extensive and varied, since it is not only limited to European cities, but also to those in Latin America, North America, North Africa and the Middle East, consolidating itself as the main air gateway of Spain to the rest of the world. Thus, it is necessary to analyze the directionality of air flows to evaluate the proportion of connectivity that transcends its immediate hinterlands. This is important, as the geographical significant of an airport, especially a large airport, is that its concept as a ‘hub’ requires it to be linked to the world urban system and the concept of a ‘global city’ (Sassen 1991). The requirement for every city that wants to be characterised as ‘global’ is that it must develop links or connections beyond its immediate hinterland. The role of air transport in these cities qualifies them as global because they are accessible from almost anywhere in the world, and any other point may be accessed from them; physical accessibility encourages its functional centrality (Córdoba et al. 2007; Córdoba and Gago 2010). Although their international air connectivity reaches very high levels at the intra-regional level (Table 1), in almost all cases analyzed, the airport hub (and therefore the city that hosts it) has a high international profile; connections and frequencies are not limited to the nearby hinterlands but acquire a long- range intercontinental character. Thus, the role played by airports in the context of globalization is crucial not only as an aviation infrastructure that facilitates landings, take-offs and other required minimum services (a basic role), but above all, because they allow the materialization of the connectivity that it is required to avoid being isolated from contemporary world flows (a defining role). [Table 1 near here] Second, airport-city symbiosis is also reflected in the ability of airports to stimulate the economic development of the cities and regions where they are located. Numerous studies illustrate this fact in terms of GDP (Neufville and Yajima 1972; Hakfoortet al. 2001, Florida et al. 2015) and employment (Debbage and Delk 2001; Sheard 2014). Other work focuses on the economic and territorial dynamics that emerge in the airport surroundings, since these are particularly relevant urban indicators of development in the 21st century (Budd 2012; Appold and Kasarda 2013; Cidell 2014), especially with the emergence of new facilities, services and sources of income. These can be classified as ‘non-aeronautical’ and extend the business scope and economic impact beyond the physical limits3. This expansion of new uses has led to the growing inclusion of the airport in the urban area, in turn favoured by a contemporary metropolitization process. Thus, new academic concepts have emerged to synthesize and describe the increasing area occupied by airports, and their increasing number of activities. These concepts are expressed in books including Aerotropolis (Kasarda 2001), Airport City (Guller and Guller 2003), Aviopolis (Fuller and Harley 2004), Airport Corridor (Schaafsmaet al. 2008), Airea (Schlaak 2010) and AeroSCAPE (Kraffczyk 2012)4. In this expansion of airport surroundings, commercial, industrial and business facilities play a significant role (Budd 2012; Freestone and Wiesel 2016). The tertiary sector has found an ideal location in airports because they are a powerful magnet to attract companies specializing in information and communications technology and other high-tech industries that are especially interested in shortening production cycles and speeding up delivery times (Button et al. 1999; Lee and Yang 2003)5. The main business areas that can be found in airports are R&D, consulting, computer services, human resource management, legal services, accounting, finance, marketing and other highly skilled business areas (Timbrel et al. 2006; Yeo et al. 2013). Many of the new industrial, production or business parks were designed to stimulate the production and circulation of intangible capital (Park et al. 2004; Cidell 2014), feed the renewal of cities and their economies, attract talent and innovation flows to/from the city (Dvir and 3 A total of $130,900 million in aeronautical revenue was attained worldwide in 2013 (ACI, 2014). Of this global revenue, 38.08% was not derived from the main role of air activity but rather from housing and commercial activities in the surrounding area. 4 Although this work does not focus on the negative externalities that arise from proximity to an airport, it should be noted that some authors criticize the airport-city model regarding its long-term sustainability and energy usage, among other issues (Charles et al. 2007). Other criticisms consider that an airport is not capable of generating the economic growth of a city by itself (Powel 2011). 5 The proximity to an airport is key in the relocation of a company since it facilitates mobility and face-to- face contact, which are still needed in certain business sectors. Thus, it is not only important to have the presence of infrastructure and transport-communication networks but also to use them in the most profitable way. This situation is deeply analyzed in actor-network theory (Latour 1987: 172). Pasher 2004; Derudder et al. 2013) and participate in the ‘knowledge economy’ (Yigitcanlar et al. 2008, Conventz and Thierstein 2014), with the aim of projecting economic growth and post-industrial development (Poungias 2009; Conventz and Thierstein 2011). Third, it is considered necessary to include a symbolic perspective for a full understanding of these infrastructures, as their representative nature, brand and image also contribute to promoting the symbolic value of cities and to positioning them on the world map (Keller and Lehmann 2006; Moilanen 2015) within the recent dynamics of a leisure-consumer society (Ritzer 2007; Bauman 2013) and cognitive-cultural capitalism (Scott 2008). According to these theories, the typically physical mechanisms of the industrial city are replaced by others of an intangible nature, such as knowledge, innovation and creativity, which are considered the new driving forces of territorial development in the post-industrial city (Scott 2014). Thus, competition between the major cities in the world leads them not only to focus on the multiplicity of economic flows, but also to emphasise particular forms of cultural capital (symbols, images) that emphasize their identity and cosmopolitan value. In this way, lending more and more importance to cultural production of space is a way to attract and sustain human and financial flows (Scott 2000; Pratt 2013). Among other methods, hosting sporting events and cultural festivals and constructing distinguished heritage structures should be highlighted. These approaches, clearly neoliberal, attempt to promote territorial competitiveness by emphasizing the identity, distinction, modernity and avant-garde quality of the site in comparison to other areas (Sklair 2012; Knox 2012; Specht 2013)6. Airports have become elements that capture such actions since their ground is trodden 6This neoliberal ideology has been adopted by some contemporary approaches of urban planning to ensure the economic growth and competitiveness of cities. However, a critical approach has considered that beyond ensuring international positioning of cities, it is necessary to ensure conditions of equity and the social welfare of citizens (Moulaert et al. 2010; among others). by millions of users every year. Architects, many of them with prestigious careers, are involved in the rehabilitation, renovation, expansion or new construction of these infrastructures, with the implicit aim of reinforcing the image of the city and the country in which they are located7. Thus, the functional and transit areas, without aesthetic qualities in the past, are now replaced by prestigious ‘laboratories’ of avant-garde architecture, where unique materials, ultramodern forms of complex architectural solutions and eclectic inspirations have become the main elements for artistic qualities to exceed the functional (Van Uffelen 2012; Corkery 2016). This observation is of particular interest in relation to a so-called ‘capitalism of fiction’ (Verdú 2003) and a so- called ‘aesthetic capitalism’ (Lipovetsky and Serroy 2015). In this sense, the shape, appearance and design of this infrastructure, in addition to being the first impression that any visitor has of the city, are carefully prepared since they are interpreted as city marketing initiatives that help to promote cities in the world urban hierarchy (Castro and Lohmann 2014). This factor of representation and image is also developed in ancillary activities of the airport, where tax-free stores show elements of belonging to the so-called ‘global’ market by displaying global brands that are easily visible in any mall. In this way, the large airport halls, waiting rooms and duty-free facilities are also shopping centres where intangible patterns of cultural globalization are staged through the dramatization of place (disneization), but are adapted to local peculiarities (glocalization). Following the development of activities related to consumption, trade becomes a pretext and purpose for the leisure time of passengers. As a result of waiting times that are endured in these infrastructures, it is not surprising that airports have engaged in this lucrative shopping business, ostensibly increasing their profits since the users are observed more 7Among others, it should be noted Richard Rogers (T5 London-Heathrow), Norman Foster (T3 Beijing Capital), Paul Andréu (Jakarta SoekarnoHatta), César Pelli (ET Tokyo Haneda), Santiago Calatrava (Bilbao Sondika), Renzo Piano (Osaka Kansai) or Rem Kolhaas (Doha Hamad International). as buyers than travellers (Geuens et al. 2004; Han et al. 2014). It is also not surprising, therefore, that ‘global brands’, considered icons of cosmopolitanism and globalization distinction (Lipovetsky 2006; Chevalier and Gutsatz 2012), are observed widely in many airports around the world (Díez-Pisonero et al. 2016). In addition to stores, fast-food restaurants and duty-free facilities, leisure is part of the art of seduction of the traveller. As a result, other recreational equipment, with clear influence from the ‘entertainment economy’ (Stevens 2007) shows the recent transformation that airports are experiencing. Examples of these changes are luxurious shopping centres (Dubai Int. and Haneda Int.), cinemas, saunas and swimming pools (Singapore-Changi), ice rinks and wave pools for surfing (Munich Int.), museums (Amsterdam-Schiphol and San Diego Int.), art galleries (Chicago-O'Hare and Atlanta- Hartsfield) or gambling areas (Las Vegas-McCarran), among others. These changes allow users to have the impression of being part of a unique experience in the purchasing process, an experience which is the stimulus that generates consumption (Miles 2012; Harvey 2013). This dynamic has opened a line of explanation that is linked to the concept of the ‘experience economy’ (Pine and Gilmore 1999). These three perspectives (operative, economic and symbolic) are all necessary to understand the city-airport symbiosis. The Adolfo Suárez-Madrid Barajas Airport constitutes a significant case study to analyze this interrelation because of its recent expansion and renovation, the multiplication of new services and activities that are being developing in its surroundings and its perception as a new landmark in the urban landscape of Madrid. Multidimensional symbiosis in Adolfo Suárez-Madrid Barajas (ASMB) Airport ASMB Airport is a Spanish public airport owned by AENA8 and located in the vicinity of Madrid, the capital of Spain. This airport is the first Spanish airport for passenger traffic, air cargo and operations (AENA 2016), and is ranked 5th in Europe and 24th worldwide by number of passengers (IATA 2016). ASMB Airport constitutes a significant airport hub on the world scene where city-airport symbiosis is observed in the three aforementioned perspectives. First, the importance of this airport is highlighted from an operational point of view since it serves as the main air gateway not only for Madrid but also for all of Spain, with its international scope extending around the world (Cubela and Costa 2013; Vílchez 2013). Its varied and intense geographical connectivity allows ASMB Airport to be positioned as one of the major European hubs and the most important European hub connecting Latin America and Europe, with 27 direct connections, representing 35% of the total international connections registered (Table 1). Two facts play a crucial role in these data from ASMB Airport. First, Terminal 4, which opened in 2006, has increased the potential capacity of the airport by up to 70 million passengers and up to 120 operations/hour (AENA 2015); and second, the representative airline of Iberia acts as a hub in the airport. Although Iberia plays a significant role in the development of ASMB Airport, the truth is that its merger with the IAG group in 2008 coincided with a moment of maximum uncertainty that presaged Madrid-Barajas experiencing the same issues as other European hubs, such as Brussels when Brussels Airlines collapsed or Zurich when Swiss Air became Swiss (Gallego 2013). At the beginning of this merger, which was contemporaneous with the world economic recession, Iberia observed reduced benefits, passengers and air 8Spain is still among the few countries in the European Union where airports are managed centrally as a fully integrated network (Bel and Fageda 2008). The airports belong predominantly to the State in the form of Spanish Airports and Air Navigation (AENA in Spanish), which manages and regulates the 48 public airports that compose the Spanish air network. links, since other airlines took advantage of the gaps that Iberia left in the South Atlantic as a consequence of its crisis (Salcedo 2015). However, after several years of adjustment (identified in its Transformation Plan9), the company returned to operation with a growth in passenger traffic and a passenger load factor that was larger than its IAG members (AENA 2013). The recovery of Iberia, which has also benefited from decreasing oil prices and AENA rates, the rebound of Spain as a tourist destination, and the recovery of Madrid as an attraction, has allowed the revival of ASMB Airport (AENA 2015). All these factors have helped ASMB Airport to return to pre-economic recession levels, reacquire some of the international air connections that were lost and therefore consolidate the airport as an inter-continental hub that supports the role of Madrid as a global city (Díez-Pisonero, 2016). Second, ASMB Airport underpins the socio-economic dynamism of the Spanish capital, as it not only generates 57,500 direct/indirect/induced jobs but also contributes to over 10% of the Madrid region's GDP, and is one of the main economic engines in Madrid and the entire country (Ayuntamiento-Madrid 2013). The area surrounding the airport has undergone important territorial transformation since its original construction in 1928; this transformation has intensified from the late 1990s to the present (Serrano et al. 2006). Perhaps the most important transformation in its history in terms of occupied area occurred in 2006, when the expansion occurred from two to four runways and the construction of Terminal 4 and its satellite (T4S) was carried out. Since then, the airport has intensified its polarizing effect on infrastructure by attracting other uses and activities, mainly residential, commercial and industrial (Gago et al. 2013). It should be emphasized that the airport environment is not a static space but is in continuous evolution. A clear example of this is the ‘Airport City of Valdebebas’, a new 9This Plan includes labour agreements with employees (layoffs and early retirements), a renewal policy of the corporate image, further promotion of its low-cost airline (Iberia Express), and a new style of management to increase productivity and ensure labour stability, among other reforms. urban development on the edge of the airport that is part of a planning initiative within a territorial strategy for economic and residential development (Valdebebas 2015)10. Research into the economic impact of the airport in the large urban area (LUA) of Madrid shows how the airport is a powerful magnet to promote the knowledge economy. This status is verified by analyzing the distribution of the companies using the OECD definition11 of knowledge economy. Following the locational patterns of other world airports (Poungias 2009; Conventz and Thierstein 2011), the largest percentage of these companies has a special interest in being close to the airport, since 33.2% of the total number of businesses located within a 10-kilometers buffer for the six corridors in the LUA of Madrid in 2015 were located in the vicinity of the A2 road corridor (which links the city centre with the airport). The same results were found by analyzing the distribution of these companies by territorial sectors between road corridors since the northeast and east sectors (between the road corridors A1-A2 and A2-A3, directly affected by the proximity of the airport) are the most dynamic, with concentrations of 25.4% and 19.5% respectively of the total number of businesses located in the LUA of Madrid (Figure 1). This concentration of activities in the vicinity of the airport benefits not only from proximity to this infrastructure, but also from the economies of scale derived from the 10 Despite the proximity to the airport, the noise impact in the City of Valdebebas is always within the limits permitted in the Municipal Ordinance (BOCM, 2015). Among other examples, a limitation developed to address this impact is the distance where buildings must be built according to the flight paths and the configuration of the tracks. 11 The OECD defines ‘knowledge economy’ as an expression coined to describe trends in advanced economies towards greater dependence on knowledge, information and high skill levels and the increasing need for ready access to all of these by businesses and the public sector (OECD 1996). Several Standard Industrial Classification (SIC) codes, grouped into three categories, are used to define the knowledge economy: high-tech industries (20, 21, 26, 30), knowledge-intensive industries (64, 65, 85, 86) and advances business services (61-63, 66, 69, 70-74). high spatial connectivity that it generates, through both the internal terrestrial road infrastructures and the external air connections (Serrano et al. 2006)12. Therefore, the airport has turned into one of the most relevant economic and urban indicators of development in Madrid in recent years. Its expansion of new uses and activities in the tertiary sector has led not only to the growing inclusion of the airport in the urban map of Madrid, but also to its participation in the knowledge economy, attracting talent and innovation flows to and from the city, mirroring the experience of other competitive international airports (Freestone and Wiesel 2016). [Figure 1 near here] Third, city-airport symbiosis may be observed in ASMB Airport from a symbolic perspective in both the architectural design of the infrastructure and the recreational activities and commercial establishments developed within it. With regard to the architectural design, Terminals 4 and 4S, led by Richard Rogers and Antonio Lamela, constitute symbolic buildings of avant-garde architecture (Sklair 2012; Knox 2012) whose specificity is found in the curvature of the roof, created from the flexibility of bamboo slats. Their aesthetic and visual values, which are key in the current so-called ‘aesthetic capitalism’ (Lipovetsky and Serroy 2015), play a major role in their recognition as urban icons of Madrid. This is inferred from the results obtained from the 150 surveys completed by airport passengers during June and July 2016, since 96% of them considered that Madrid-Barajas airport is already a new icon in the skyline of Madrid. However, although there is widespread recognition of the airport as a new urban landmark, most respondents (92%) believe that this infrastructure does not identify the 12 It should be noted that this correlation is not causation, as other authors remark, the inauguration of an airport, by itself, is not capable of generating the economic growth of a city since transport systems are social products that respond to an economic and political system that demands the widest possible connectivity conditions (Chesnais, 1980; Gago, 2003). essence of Madrid, one of the most recurrent problems in the construction of the urban image in the city (Canosa and Garcia 2012). Most respondents agree that the curvature of the roof or the use of bamboo are interesting mechanisms to "iconize" this airport and differentiate it from others. Nevertheless, they are insufficient mechanisms to define the denomination of origin of the place, as happens in other international examples around the world. For example, the Rocky Mountains were the inspiration for the roof form used in the Denver Airport; Korean culture is showcased with a design inspired by a traditional Korean home at the airport in Seoul-Incheon, and the shape of a dragon in reference to one of the greatest emblems of Chinese culture is used on the roof of Terminal 3 at the Beijing Airport (Díez-Pisonero et al. 2016). This lack of identity in the architecture of the ASMB Airport is observed in the data, as only 6% of respondents chose the airport as the main urban icon of Madrid. Other landmarks were repeatedly picked first such as the Puerta de Alcalá, the Cibeles fountain and the Santiago Bernabéu stadium. This highlights two facts: the reduced weight exercised by the airport as the main iconic landmark of Madrid and the lack of a symbolic building that clearly identifies the capital of Spain, as happens in other cities of the world with other representative urban icons (Castillo-Villar 2016). In addition, although this infrastructure has redefined Madrid's new skyline, most respondents (89%) recognize that this iconic architecture does not exert a significant role for passengers to select this infrastructure as a hub. Other factors over the architecture prevail when choosing an air hub, such as the availability of hourly frequencies and the airlines present at the airport, among others. This symbolic perspective of the city-airport symbiosis can also be analyzed in the recreational and commercial establishments developed within it: from being simply a place for landings and take-offs, the airport has become a place in itself, full of restaurants, stores and entertainment establishments where one can consume and have fun, predominant activities in the leisure-consumer society (Ritzer 2007; Bauman 2013). In recent years, the commercial activity at the ASMB Airport has increased significantly in both commercial opportunities and income (AENA 2014). Two new commercial spaces (The Fashion Gallery and the Mad Fashion Hub) bring together many global brands, causing the airport to resemble a shopping centre. Although none of the respondents admit to going to the airport with the sole purpose of buying (as is the case for inhabitants of Amsterdam who live near airport13), the truth is that most (95%) admit having visited these stores before, after or between flights. Additionally, bars and restaurants where local gastronomic specialities are served have recently been opened at the airport. GastroHub, La Bellota and Mahoudrid are places where beer from Madrid, Iberian ham and other typical Spanish tapas can be tasted, highlighting the ‘exaltation of the specificity of place’ (Robertson 1992; Friedmann 2005). Almost all respondents (99%) suggest that, if they had time between flights they might go to the city centre to taste these products; without that time in most cases, they (especially international passengers) are very positive about these opportunities to experience the gastronomic essence of Madrid within the airport. Passengers from Latin America, particularly appreciate these catering spaces, demonstrating this additional role of ASMB Airport as a gateway to the Iberian region. Other leisure facilities have appeared in recent years providing diversions for passengers during waiting times: museums, spas, betting shops and nurseries, among others. Thus, the possibility of being able to have experiences linked to entertainment and consumption in such transport infrastructures, questions the anthropological 13 Many inhabitants of Amsterdam who live near Schiphol go to the airport especially on Sundays and at night when most retail stores in the city are closed (Conventz 2008). consideration of these places as inhospitable and without identity (‘non-places’ by Augé 1993), and instead identifies them as ‘places of globalization’, defined, or are at least heavily influenced, by prevailing vectors in current society: leisure, consumption and global mobility. Conclusions The airport and the city constitute a required symbiosis; that is, there is no global city, that does not have a large airport and vice versa since both elements interact, provide feedback and are mutually supporting. This interrelation is observed in terms of three connecting dimensions. First, cities with large inter-continental air hubs provide the most visible examples of airports being necessary conditions for cities that seek to be part of world mobility. These large airports not only allow the materialization of the connectivity that every city requires to provide intense contemporary global linkage, but are also exponents of functional centrality as they ensure the connectivity beyond their immediate hinterland that is considered an essential feature in defining a ‘global’ city (Sassen 1991). In Madrid, ASMB Airport is an excellent example of this connectivity, since it is the main air gateway of Spain to the rest of the world and it has become the most important inter-continental European hub connecting Latin America and Europe. Second, it has been argued that city-airport symbiosis is also embodied in economic dynamism since airports are able to generate local employment and attract economic activities, as an economic hub. These hubs are not related to traditional productive sectors; instead high-tech and knowledge-intensive activities play a significant role. Thus, ASMB Airport has become not only one of the most representative urban indicators of development of the city, but is also one of the most important economic engines after it has expanded to promote the knowledge economy, especially in those main route corridors and territorial sectors close to the airport; this follows the example of other international and competitive airports. Third, this paper has also analyzed the symbolic connotations acquired by airport infrastructure. Non-aeronautical uses are increasingly dominant in these places, causing a change in philosophy in their design and their activities. The morphological changes associated with avant-garde architecture are interpreted as city marketing initiatives that claim to build a modern and attractive image of the territories in which they are located. Although Terminal 4 of ASMB Airport has neither defined the essence of Madrid nor has become the main urban icon of the host city, it is considered a new landmark in the skyline of Madrid that has reinforced the innovative image of the capital of Spain. Additionally, it has been observed how airports, ASMB Airport among them, have become scenes of leisure consumption practices, with characteristics similar to those of a mall, and contribute to designing territorial identities, despite the homogenizing power of this architectural form in design patterns and the leisure/consumption activities that are carried out. The previous pages converge into a final thought regarding the anthropological interpretations that define airports as ‘non-places’ (Augé 1993); rather, we consider them as vectors of contemporary mobility and as one of the ‘places of globalization’ that are defined, or are at least heavily influenced, by the contemporary emphasis on leisure, consumption and global mobility. Thus, these ‘places of the 21st century’ are formed according to the needs of globalization and the demands of the mobile classes who spend long hours in transit. These places provide the city where they are located with prestige, reputation, centrality and internationalization, as well as competitiveness in climbing the world urban hierarchy (Smith and Timberlake 2001; Redondi et al. 2011), something which has occurred in recent years in Madrid. 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