Karlsruhe is a rare example of a city still largely organised around the enlightenment conception of the “ideal city”. The city grew around the Karlsruhe Palace and as a result it is divided into two, with the densely packed blocks of the city centre to the south of the palace, and a “green city” of parks and forests to the north. MVRDV’s masterplan blurs this distinction, filling a void within the city blocks while also bringing more greenery to the southern half of the city.

MVRDV’s proposal resulted from an intensive process of public participation, with each step in the urban framework responding to the desires of the public. The first step in developing the masterplan was to imagine the area filled with four-storey blocks, matching the heights of the city blocks to the north. From this starting point, these blocks are “carved” to create the necessary spaces for the city: A plaza is created to preserve the approach to the Badisches Staatstheater; established trees are preserved by carving the blocks to fit around them; two diagonal streets are added to improve connections; and courtyards are created within the blocks as required.

On the four-storey blocks, each façade is different in character, with building owners and stakeholders able to bring their own flair to the district. The rooftops of these new blocks will be densely planted to create a rooftop forest, with stairs and bridges making it an accessible urban park, contributing to a reduction in the urban heat island effect.

The masterplan was created with careful consideration given to the future of the district administration office (Landratsamt) of Karlsruhe, which is currently housed in an outdated modernist tower on the west of the masterplan site. The plan allows for a phased move to the low-rise block that would occupy the same area, after which the tower could be either renovated as residential apartments, or demolished and replaced. A further alternative offers a scenario in which the district administration office would move into a new building hovering over the Ettlinger-Tor-Platz – replacing the floating garden – after which the Badenwerk high-rise could also be either modernised or replaced. Other locations in the masterplan are also identified as ideal locations for the future addition of residential high-rises, contributing to a more lively city centre by improving the area’s mix of functions.