Centre and Periphery

More than half of Germany's population has long become accustomed to living and working in the urban "sprawl" – the Zwischenstadt. Since the publication of the eponymous book in 1997, the term Zwischenstadt has entered linguistic usage not only in German but – since the book's translation – as a foreign import in English, French and Japanese as well. Coined by Thomas Sieverts, it denotes areas, many of them just a few decades old, which are neither city nor countryside but which are unlike what we think of as suburbs.

Zwischenstadt means sprawl: the patchwork proximity of unconnected and highly disparate elements which vary in function, scale and use. It describes the hotch-potch on the margins of the metropolitan landscape – shopping centres alongside family homes next to a motorway, for example – but it also denotes a more general structure which is "undermining" the historical norms of city life. In historical terms, the Zwischenstadt is a newcomer, an interim stage in the transition to an uncertain future.

The Zwischenstadt – although seemingly an amorphous mass of built-up space – has characteristic features. Dominated by large-scale, isolated, "autistic" systems, its form is "fractal" – in other words, it forms an extensive margin and close linkages between settlement and open space. Many families want to live near open spaces but need to be close to the amenities afforded by settlements in order to satisfy their every-day needs, such as access to the regional labour market via the local transport systems. Often, the Zwischenstadt seeps into the greenfield sites that surround the metropolitan area. This causes conflicts with farmers, for settlement growth deprives agriculture of land. In some ways, the Zwischenstadt is a "new frontier" – the last stretch of wilderness between the culture of the city and the cultivated countryside, a space for new and unadapted lifestyles and patterns of work, a place where people can still tinker and try out new ideas without promptly being subjected to tight bureaucratic controls.

A child of the post-war era

The European form of the Zwischenstadt could not have developed without the historically unprecedented wealth and prosperity generated in the post-war era. With purchasing power soaring since the 1950s, per capita built-up area has tripled. Leisure time has doubled, triggering a strong rise in demand for recreational space and sports amenities, and individual mobility has also increased to an undreamt-of extent. This explains the massive spread of settlement areas – but this is not matched by a comparable rise in population. On the contrary, population density is steadily decreasing as a result.

The rise in wealth and prosperity is unlikely to continue: in future, many people will earn less and have to work for longer, and individual mobility will become much more expensive. Combined with an increased percentage of older people and the substantial depopulation of some areas of East and North Germany, a re-concentration is likely to take place, not only in the old town centres but also around the local railway stations, for example. But the Zwischenstadt is unlikely to disappear. Despite stagnating and even falling populations, the rise of the Zwischenstadt cannot be reversed. Wherever it is served by good local public transport networks, it will become even denser. The well-established settlements which currently cater for the nuclear family will have to be adapted to the needs of an ageing population, and farming, too, will need to adjust in order to provide services for the urban populations.

An international phenomenon

The Zwischenstadt exists in various forms all over the world. Superficially, the major conurbations are similar: apparently diffuse and expansive, and encompassing many urban centres. But appearances are deceptive: the conditions which encouraged the emergence of the Zwischenstadt and its underlying socio-economic structures vary very widely. In the developing countries, for example, its populations are involved in small-scale food production and the informal economy – one outcome of the poverty of the incomers flocking into these areas.

The dependence on the urban core also varies widely; there is a tendency everywhere for the Zwischenstadt to cast off its links with the core cities and take on responsibility for performing the requisite functions itself; this is apparent in Germany, for example, where more than half the population has long become accustomed to living and working in the Zwischenstadt.

But politics and administration have yet to catch up with this lifestyle shift, which embraces the entire metropolitan area without regard for municipal boundaries. The wrangling over which political and administrative structure is appropriate to cope with the Zwischenstadt is a feature of political debate in many metropolitan areas, but few of them have so far managed to implement an administrative reform which does justice to the new regional and therefore inter-municipal context. Hanover and Stuttgart are good examples.

Good starting points for targeted urban restructuring

The main shortcomings of the Zwischenstadt are threefold:

• In general, they are too motorway-dependent and therefore relatively inefficient in transportation terms.
• They are short on aesthetic appeal and are therefore not recognised as part of our culture.
• They are fragmented in political and administrative terms, which means that they cannot fulfil their major potential (e.g. regional burden-sharing, prioritisation, joint development of regional parks and industrial estates, etc.).

However, these shortcomings are even more striking in other parts of the world, where the conurbations tend to be even larger.

The European forms of the Zwischenstadt, on the other hand, offer very good opportunities which simply have to be seized and exploited. They offer large open spaces which are generally within easy walking distance of the housing areas. They have basic local public transport which offers scope for improvement, and to some extent, they are repositories of history, which contributes to their unique profile. All these are good starting points for targeted urban development. The Zwischenstadt is a legitimate off-shot of the European cities; its quality of life reflects a chapter in our culture in which – in our knowledge-based economy and in the global competition for intelligence and purchasing power – is becoming increasingly important.