IJmuiden, port of Amsterdam and part of the gemeente (municipality) of Velsen, western Netherlands. The port is situated at the western end of the North Sea (Noordzee) Canal, which was opened in 1876. IJmuiden is also an industrial centre with fertilizer and cement factories, and it is an important fishing port with a government fish market. Three huge locks at IJmuiden link the canal to the North Sea. Two breakwaters project seaward from the canal mouth for nearly 1 mile (1.6 km). Used as a base for German torpedo boats in World War II, its facilities were damaged by Allied bombing but have since been rebuilt.