The ruins of the fortress Krassen Kale are located at hill around 3 kilometers north-east of village of Buta. It probably dates back to X-th century. There are several preserved parts of the fortress including buildings, inner and outer walls some of which are 6 meters high.
A precious find was discovered in the fortress during archaeological research in 1987 - a medallion-stamp of the fortress` last ruler Rafail. The stamp is the only known object which belonged to a Bulgarian noble of that time.