The IJ [ ɛi̯ ] was originally an estuary of the Zuider Zee in North Holland and is now separated from this. It separates the Amsterdam city center of Amsterdam North.
The name is derived from the Germanic IJ words Aa, Ae, or for the " water or water". In Dutch, the name consists of the digraph Ĳ, which is regarded as a single letter, and therefore both are always capitalized together at the beginning of a word when substituted by the two-letter IJ.
During the Middle Ages dikes were built along the IJ. Along the south side, later replaced by the Amstel River to the east, the Sint Antoniusdijk, by the Hoogte Kadijk, the Zeeburgerdijk and Diemer Zeedijk. To the west of the Spaarndammerdijk and Haarlemmerdijk lie. On the north side is the Noorder Ijdijk. Towards the end of the Middle Ages came here the dike villages Durgerdam Schellingswoude, Nieuwendam and Buiksloot.
Mid-19th century, it was decided most of the estuary, the westward extended as far as Velsen and Beverwijk, einzupoldern, and the rest by a causeway from the Zuiderzee dam up. The same time -scale North Sea Canal connects the Completed - IJ with the also newly created port of IJmuiden. The outer - IJ is located on the east side of Orange locks and is connected to the IJsselmeer and the Marker lake. North of Spaarndam is still a part of the non eingepolderten estuary.
At the level of the previous Amstel mouth three islands were built in the IJ. For this, the sand from the dunes was used in IJmuiden, which was dug up when creating the North Sea Canal. On these islands the Amsterdam Central Station ( Centraal Station ) was built; by the city of Amsterdam was separated from the IJ and moved the port area.
In the eastern part of the Terminated - IJ end of the 19th century was built on artificial peninsulas eastern port area. End of the 20th century, a residential area was built there. In IJ is working on the new district IJburg for several years, which is also on aufgespültem country.
Before we began the construction of the harbor America, a polder was created, in which the three islands Ruigoord, DeHoorn and Jan Rebellenwaard were.
In IJ is the Fort Pampus, part of the former Fort Amsterdam, built on an artificial island.
The water level of foreign IJ is held together with the marker Sea and the IJsselmeer in the summer on NAP -0, 40 m and in winter on NAP -0, 20 m using Spülschleusen and pumping stations, with NAP stands for the Normal Amsterdam Level. The IJsselmeer is the largest freshwater pool in the Netherlands and is used for drinking water supply of more than one million inhabitants.
Since 1897, there is a regular ferry service between Centraal Station and Amsterdam-Noord. Earlier still wrong car ferries, today only pedestrian ferries. The traffic is now run on the three tunnels Coentunnel, IJtunnel and Zeeburgertunnel as well as a road bridge, the Schellingwouderbrug.