The smal River Eider has a total length of 188 km, but is navigable from Rensburg only. The navigable part starts right in the middle of the town of Rensburg, it is there not connected to the Nord-Ostseekanal which runs parallel to it. This connection is made with the Gieselaukanal in the northwest of Oldenbüttel only.
It offers a romantic tour through the marshland in the middle of the flat, north German landscape of Schleswig-Holstein.
The navigable Treene
River Treene is from the lock to the Eider in the south of Friedrichstadt until Kellighusen conditionally navigable.
Gieselaukanal
Since River Eider doesn’t have a connection to the Nord-Ostsee-Kanal at Rendsburg, it was established 20 km later, in the southwest with this 3 km long canal. The Gieselauer lock is one km before the confluence into the NOK.