The Kromme Rijn (Dutch pronunciation: [ˈkrɔmə ˈrɛin]) ("Crooked Rhine", for its many bends) is a river in the central Netherlands. In Roman times, this northernmost branch of the Rhine delta was the main distributary of this major European river. Along its banks the Romans built their frontier castella part of the Limes Germanicus. Since the Middle Ages, however, the stream lost its importance as it silted up, and eventually it is nearly cut off from the Nederrijn-Lek main artery. Yet it retained the name "Rhine".