Barnacken, Summit in the Teutoburg Forest, North Rhine-Westphalia, Germany

Barnacken is a 446.4 m hill in the Teutoburg Forest, the highest point of that ridge in North Rhine-Westphalia. Its summit lies about 3 km southwest of Horn, a district of Horn-Bad Meinberg. The hill has several spurs: the Kleine Rigi (387.7 m) to the north-northeast, the Kartoffelberg (about 385 m) to the east, the Mordkopf (408.6 m) to the west and the Padberg (437.5 m) to the south. A trigonometric point is marked on topographic maps a few metres east of the summit at 446.1 m.

The Teutoburg Forest is known for a battle fought in 9 AD, when Germanic warriors defeated three Roman legions in the area. That event shaped how this whole region was remembered and named for centuries afterward.

The name Barnacken is used for the whole ridge crest, and the summit marks the most southeasterly point of the Weser-Ems watershed: streams rising northwest of it reach the Ems, those flowing north and east reach the Weser, and those south of it drain via the Lippe into the Rhine. Walkers on the B 1 pass the saddle of the Rhine-Weser watershed at 319.8 m just southeast of the top.

The summit is reached by several marked hiking trails that start from different points around the area. A shelter near the top works well as a reference point and a place to stop before or after reaching the highest point.

Barnacken sits on a water divide, meaning that rain falling on one side of the summit flows toward a completely different river system than rain falling on the other side. This makes the top a natural boundary that is invisible to the eye but very real in terms of how water moves across the land.