Jewish Museum, Berlin

Chep Lak Kok Airport, Hong Kong

Architects and developers are using old spaces to invent new ideas for 21st-century living.

Chep Lak Kok Airport in Hong Kong, for example, is not just a place for planes to land but a whole city built on an island in the middle of the sea. In Hong Kong, where every square inch of land in the city is used and high-rise buildings are piled up to save space, an airport built offshore uses new land effectively. The development is a consumer's paradise – where shopping and leisure can be combined with travel.

At Duisberg-Nord in Germany a vast industrial site has been transformed into a park. But not a traditional park – the old factory buildings are intact, toxic waste has been used to encourage different species of plants to grow, and broken machinery is used to decorate the park. It is used by scuba-divers, nightclubbers and botanists... a wide range of people have found exciting aspects not normally found in a traditional park.

Architecture is often bound up with politics – look at the redevelopment of Potsdamer Platz in Central Berlin. Before World War II, this part of the city used to be a favourite place for Berliners to meet, socialise, eat, drink or go shopping. After the war, when Berlin was split by the Berlin Wall, it became a site of devastation. Nothing remains of Potsdamer Platz as it was but now that Berlin is one city again this important area has been transformed into the new civic heart of the city.

Dramatic buildings have risen from the rubble and the city has a completely new district. One of the buildings which has been created is a Jewish Museum. This is a controversial political development because of the Holocaust. In less than 50 years, Berlin has changed from being the centre of Nazi ideology to offering a monument to Jewish history and culture. This is a very important political shift.