The "Altburg" near Bundenbach is one of the most researched Celtic hilltop settlements of Central Europe. Located at a horseshoe bend in the river on the western bank of the Hahnenbach, the site is not only hidden by high mountain ridges all around but is also protected by steep slopes to the north and east. The natural main access route runs over the hilltops from the west to the mountain ridges. The inside area of the castle hill is enclosed by a still very impressive 80 m long and 7 m high partial fortification with moat. Between 1971 and 1975, the Celtic hilltop settlement was completely excavated by the Rheinische Landesmuseum Trier (Trier regional museum). Between 1985 and 1988, the palisade enclosure near the so-called upper-castle (Oberburg) and a few groundplans of houses, storehouses and watch towers were reconstructed.