Burg Everstein, Medieval castle ruin in Negenborn, Germany

Burg Everstein is a two-part hilltop ruin on the Grosser and Kleiner Everstein (345.2 m and 305.1 m) in the Burgberg ridge north of Bevern. The Kleiner Everstein plateau, about 60 m long and 30 m wide, is ringed by a 2–5 m high wall and a rock-cut ditch; at its south end lie the mortared Muschelkalk foundations of a tower. On the Grosser Everstein, a 6.5 × 12.5 m palas was excavated in 1966.

The Kleiner Everstein was probably built around 1100 as the original seat of the Counts of Everstein, while the Grosser Everstein was added around 1170. Both hilltops were fortified by 1265, when castrum Everstein maius is documented. After a successful siege in 1284 the site passed to Duke Heinrich I of Brunswick-Grubenhagen, who converted the Grosser Everstein into an administrative seat. In 1443 a siege by the Duke of Brunswick largely destroyed the castle, and in 1493 the monastery of Amelungsborn obtained permission to demolish it.

The name Everstein comes from the two hills, the Großer and Kleiner Everstein, on which the castle was built. The Kleiner Everstein plateau is enclosed by a 2 to 5 m high wall with a rock-cut ditch, while the Großer Everstein preserves the 6.5 by 12.5 m palas excavated in 1966. Finds from the excavation include spurs, crossbow bolts and knives.

The two castle sites sit on the summits of the Grosser Everstein (345.2 m) and Kleiner Everstein (305.1 m), the latter 500 m north-northeast of the former, between Arholzen, Bevern-Lobach and Negenborn. The Kleiner Everstein plateau measures about 60 by 30 m and is ringed by a wall still 2 to 5 m high; the Großer Everstein lies on a roughly triangular plateau whose western approach is blocked by a cut through the rock.

A television transmission antenna from a much later period still stands inside the castle grounds today. Archaeological finds including medieval spurs and crossbow bolts reveal details of daily life in that era.