The Pobitia Kamak natural landmark is located on the territory of the village of Sarnitsa, the municipality of Mineralni Bani, and it covers an area of 1 hectar. It is a complex of interesting rock formations. The prehistoric fortress from Thracians times “Golamoto Gradishte” is located 1.5 km north of the village of Gorno Bryastovo, Municipality of Mineralni Bani, and it was built of large rubble stones without mortar. It is elliptical, and its walls, 2.5 m thick on average, are in a state of collapse. It is 150m long and 50m wide, it has built-up area of 5-6 decares and it has two internal walls.