The birdhouse, called Vogelstad (Bird City), was inspired by the diversity and large numbers of birds living in cities. Visser designed the structure to be hung on the side of buildings or on unused walls.
Vogelstad aims to integrate various species of birds. Each house is made to a different specification and features correctly sized entry holes. There are groupings of same-sized houses for species that roost together and single houses for more solitary birds.
For more about how urbanites adopt rural activities read our Rurban Revolution macro trend.