Doberg, Nature reserve and protected geotope in Südlengern-Heide, Bünde, Germany

Doberg is a 48-hectare nature reserve in Südlengern-Heide, a district of Bünde, rising about 30 metres above its surroundings to 105 m above sea level. It is not a true hill but a fissured landscape created by marl quarrying, with meadows, blackthorn-covered slopes, woodland and a small marshy area. The Dobergmuseum in Bünde displays its Oligocene fossils.

Marl was dug here for field fertiliser from the 18th century. In 1911/12 Friedrich Langewiesche found the skeleton of a sea cow (Anomotherium langewieschei) and the skull of an early whale (Eosqualodon langewieschei); both are shown in the Dobergmuseum in Bünde. The site has been protected since 1912 and became a National Geotope in 2019.

Locals say "im Doberg" rather than "auf dem Doberg", because the hollows and slopes were carved out by marl digging, not formed as a hill. Until the 1960s a regular open-air stage play was held on one of the meadows. Today the reserve is managed by the Kreis Herford and its dry grassland, with 61 species of wild bees recorded, is what visitors come to see.

The southern slopes are best for observing wildflowers such as Wild Carrot, Stemless Thistle, and Thyme. Visitors should wear sturdy footwear, as the terrain is uneven and can become slippery when wet.

The Doberg is the stratotype for the Oligocene epoch: nowhere else in the world are the Oligocene strata known to be so complete and well preserved. In 2019 it was added to Germany's list of National Geotopes, and 61 species of wild bees have been recorded on its dry meadows and sunlit marl cliffs.