Cities Grow by Adding Centres, Not Erasing Them

There is a persistent idea in urban debates that cities must choose between growth and heritage. The evidence from successful cities suggests the opposite. City centres do change over time, but they rarely need to be torn down to make that change possible.

It helps to start with a basic distinction. Towns often revolve around a single central square or main street. Cities, by contrast, function as networks of centres. As technology, transport, and construction techniques evolve, new centres emerge alongside older ones, linked together by increasingly efficient transport systems.

Historic areas are usually products of the building technologies of their time. Edinburgh’s Old Town, for example, reached the limits of medieval construction long before the city stopped growing. Rather than demolish it, Edinburgh expanded into the New Town, created with newer techniques and a different layout. The centre of gravity shifted, but the Old Town remained intact and alive.

The same approach can be seen today in places like Freiburg, where post‑war growth was channelled into new districts such as Vauban, allowing the historic centre to continue operating without being forced into unsuitable intensification. This reflects the long‑standing advice of urban economist Alain Bertaud, who argues that historic areas can be worked around, not forced to perform like modern high‑density districts. Street patterns, plot sizes, and existing buildings set real limits on what makes sense.

Importantly, there is no technical formula for deciding what must be preserved. These are value choices, made by the people of a city. The role of planning is to respect those choices and find ways to grow around them. The vast majority of Auckland’s buildings are not recognised for their historic value and yet Plan Change 120 keep most of the metropolitan area low rise even when close to bus routes.

It is normal for newer areas or brownfield developments to be taller than older ones. Vienna strictly limits heights in its historic districts while accommodating density in outer districts and along transport corridors. Seestadt Asper is Vienna’s answer to Whenuapai. It transforms a former airfield into a high density, walkable mixed-use low traffic neighbourhood with 20,000 homes, services, schools and jobs designed around a new rail station (built before the houses). Other suburbs, Sonnwendviertel, Nordbahnhof, Kagran / Donau City have been developed in a similar way.

Many planners argue it is hard to retrofit established suburbs to become mid or high density. They say it is much easier to masterplan high density at the start. There are a few examples of mid-density masterplanning in New Zealand. The Wynyard Quarter, Stonefields and Hobsonville are successful mid-rise developments and the Carrington development has similar aspirations. Drury and Whenuapai however seem frustratingly low-rise - these are costly to service and require a car which is expensive. A high density masterplanned development is yet to emerge. Will the crown land on Lincoln Road offer an opportunity to integrate transport with land use effectively?

In London’s Lewisham, recent development around the station is significantly taller than the surrounding Victorian neighbourhoods, precisely because it has the transport capacity and fewer heritage constraints. Height and intensity follow transport and modern construction, not historic cores.

Cities do not stay vibrant by freezing themselves in time. They do so by adding capacity where it fits best, allowing centres to multiply, and letting history and growth coexist—side by side, connected, and deliberately planned.