Once an expanse of asphalt, Tasinge Square in a suburb of Copenhagen, Denmark is now an oasis of green. Grassy lawns have taken over tarred surfaces and trees have taken root, creating a refreshing space that is drawing families to gather there.

The square, however, is not just a patch of green haven; it is also an ecological feature as in the ground is a storage tank to hold stormwater in times of downpours, to prevent flooding there and in downstream neighbourhoods.