Westhessische Senke
The tectonics of the Upper Rhine Rift, which continue along the eastern edge of the Rhenish Massif as far as the Upper Weser Hills, form highlands and lowlands here that merge into the volcanic East Hesse Highlands beyond the West Hesse Depression on their eastern perimeter. The ridges never attain the height of the loftiest peaks of the highlands to the east and west.