Among several other smaller areas here is Ith, THE northern German climbing area. Hidden in the forest are many sectors with world-class limestone and routes of all grades. The protection can sometimes be a bit hairy, or you may need to place your own gear on some routes, but the quality of climbing is high. The area is frequented by Dutch, Danish, and northern German climbers as it is the closest real rock they have. However, for years there weren't any guidebooks available for the area, so the traffic was limited. As of 2013, there is a new guidebook
which describes access to thousands of routes in this large area.