To the east of the long ridge of the Tönsberg are the ruins of a pre-historic hillfort (Sachsenlager) and a chapel known as the Hünenkapelle. The fortification was probably used until the 9th century as a defensive site and refuge. The chapel would have been built in the time when Christianity reached the Saxons under Frankish rule. The name Tönsberg could go back to Holy Anthony, in whose honour the first Christian chapel could have been dedicated.