The ruins of Scharfenburg Castle can be seen from afar on a Zechstein cone overlooking the village of Thal. First mentioned in a document in 1137, it was the object of exchange and dispute between various noble families for many centuries. The keep of the castle complex can be visited as an observation tower with information boards in the entrance area. Parts of the former castle wall, parts of the gate and moats are also worth seeing. The lookout tower offers visitors a unique view of parts of the Thuringian Forest, surrounding villages, Wartburg Castle and the Hörselberge mountains. The castle complex can be reached via the Scharfenberg promenade and easy hiking trails.