Sandgrube im Jagen 86 des Grunewaldes, Protected nature reserve in Charlottenburg-Wilmersdorf, Germany.

Sandgrube im Jagen 86 is a 13-hectare nature reserve in the Grunewald forest, formed from a gravel pit mined from 1966 to 1983. The pit left an open area of about 18 hectares with slopes up to 25 metres deep. Today the floor holds bare sand, dry grassland, shallow ponds and wet willow carr, with south-facing slopes kept open by clearing.

Between 1966 and 1983, sand was extracted here in an open-pit operation to supply Berlin's construction industry, which created the hollows and slopes that still shape the terrain today. After closure, the land was left to recover on its own and was eventually designated a protected area.

The name "Jagen 86" refers to an old forestry parcel in the Grunewald, a numbering system still used today to identify sections of the forest. Walking through the area, visitors can see how sand, water, and shrubs exist side by side within a small space.

The site is reachable on foot from the Grunewald forest, with some paths running directly along the sandy slopes. Sturdy footwear is a good idea, as the ground is sandy and can be slippery in certain spots.

Fences were put up in the sand pit so that ground-nesting bees and wasps can develop undisturbed while the site stays open to visitors. The insects nest in the dry, vegetation-free sand of the pit floor, not along the water. Three information boards explain the gravel pit, the wetland and the heat-loving fauna.