Amsterdam Netherlands Europarking Europarking - popularly known as "de billen van Zanstra - (Zanstra's buns) was designed by Piet Zanstra and built in 1971. The ground floor of this seven-storey parking facility is reserved for buses. The remaining six are connected to the street by two ramps for incoming and outgoing vehicles in the shape of a double spiral. Popular with skaters, the building took on an additional duty in 2002 when ten containers for housing the homeless were added to the ground floor.