Amsterdam is the largest port in the Netherlands and one of the largest ports in the world. The city has been one of the most important commercial centers on the map of Europe since the 16th century. Thanks to the system of canals it was possible to transport goods easily from the ships directly to warehouses, which were on the top floors of the merchant houses. Due to limited space, there are terraced buildings in Amsterdam built one next to another, which reach the height of at least three or four floors. Large rectangular windows, which were meant to provide more light for the interior, are typical for such houses.