The Großer Heineberg is a 56-meter hill in Potsdam-Bornim (peak at 52.435010, 12.988588, map below). After WWII it was used as a dump for building materials, and while the vegetation has generally made a comeback the soil is still filled with pieces of brick, tile, and glass, with larger piles of rubble appearing frequently.
The hill also has a number of permanent structures in varying states of burial / ruin, including several below-ground bunkers on the south side, a large vine-covered concrete structure on the west side, and a huge sunken foundation to the east, the concrete walls of which are covered in vines in the summer that give it a temple-like appearance.
Further to the northeast, bordering the highway, an abandoned metal building remains mostly intact, though its sides have been pulled open and a chaotic mix of furniture, insulation, and garbage remains inside.
A diverse array of vegetation springs up in the warmer months, softening the harsher edges of the brick-and-concrete heaps and attracting insects.
Access via Am Heineberg, paths from the west or south.
Vegetation near the peak can be dense in the late summer / early fall, making access more difficult.