The land price was too high due to the traffic of goods along the Amstel's canals, so the most lucky could only buy a piece of land of the size of a room and build a small house. No space to bring furniture inside the house, so the Amsterdamians invented a transportation system on top of the houses to lift the furnitures and reach the apartment windows. Due to the limited space between the canals, the bicycle was the best and favourite way to move around the city.