Spain’s Urban System: Structure, Hierarchy, and Intercity Relations
Spain’s Urban System
Characteristics of the Spanish Urban System
The Spanish urban system is a network of interconnected cities. It comprises distinct elements—the cities themselves—and the relationships established between them.
Elements of the Urban System
City Size
The population size of Spanish cities is determined by the rank-size rule, which assigns a ranking to each city based on its population. The largest population corresponds to 15 urban agglomerations exceeding 500,000 inhabitants. A large number of cities have populations between 150,000 and 400,000. The territorial distribution is characterized by the central location of Madrid, the largest urban agglomeration, surrounded by major urban areas in the periphery, and a less urbanized interior with medium-sized and smaller cities.
Urban Functions
Cities perform socio-economic activities that extend outwards. Based on their primary function, cities can be categorized as primary, secondary, or tertiary, although large cities often have multiple functions.
- Primary Cities: Specialize in primary sector activities, such as agriculture and mining.
- Secondary Cities: Specialize in industry or construction (e.g., Barcelona, Málaga).
- Tertiary Cities: Specialize in services, which define a city’s reach and influence. These services include business, finance, commerce, and transportation.
Area of Influence
The outward functions of cities transform them into central locations providing goods and services to a surrounding area of influence. This area expands with the diversity and specialization of urban functions, which can be national, regional, sub-regional, or local.
Spanish Urban Hierarchy
Population size, functions, and area of influence determine the hierarchy of Spanish cities. The following categories are distinguished:
- Metropolises: Metropolitan areas are at the top of the hierarchy. Their population exceeds 200,000-250,000 inhabitants, and they perform diverse and specialized functions with a wide area of influence.
- National Metropolises: Madrid and Barcelona, with populations exceeding 3 million, have the most diversified functions, highly specialized services, numerous multinational companies, and high-tech industries.
- Regional Metropolises: Valencia, Seville, Bilbao, Málaga, and Zaragoza, with populations between 500,000 and 1.5 million, have diversified functions and specialized services, a regional area of influence, and strong ties with national metropolises.
- Sub-regional Metropolises: Smaller metropolitan areas like Valladolid and Pamplona, with populations between 200,000-250,000 and 500,000, have diversified functions and services.
- Medium-Sized Cities: With populations between 50,000 and 200,000-250,000, their functions are less diversified and focus on business, administrative, and social services. They serve as hubs within a dense bus network connecting with nearby towns.
- Small Cities or Towns: With populations between 10,000 and 50,000 (e.g., Astorga), their functions are limited and specialized, although some may have specific expertise.
Urban Relations in the City System
Cities within an urban system are interconnected. These relationships are measured by economic flows, movement of people, and other types of flows. Unidirectional flows indicate domination and subordination, while bidirectional flows suggest integration and competition.
The Spanish urban system’s intercity relations are characterized by the following:
- Madrid: Maintains strong relationships with other cities, especially Barcelona.
- Barcelona: Has a generally weaker influence, although intense in the eastern peninsula and the Balearic Islands.
- Northeast Quadrant: Represents the largest area of integration due to the strong relationships between its five main cities (Madrid, Barcelona, Valencia, Bilbao, and Zaragoza).
- Other Areas: Relationships between cities are weaker and incomplete, with predominant flows between cities and rural areas or nearby towns. The largest disconnected area surrounds Portugal, excluding Galicia.