Drežnička Gradina

Drežnička Gradina is a mountain in western Serbia, located between cities of Požega and Užice. Its highest peak, Gradina, has an elevation of 932 m above sea level. On the cone-shaped hilltop, there is a small stone-built pyramid erected as monument to Yugoslav Partisans died in a battle against German forces in August 1941, at the time of the Republic of Užice.
A prominent feature on the mountain is the cave Potpećka pećina , located near the village of Potpeće. Its main entrance, 72 m tall, is the largest of all caves in the Balkans. Seen from the inside, the main entrance resembles the shape of the mammoth. Apart from the main, upper entrance for tourists, there is a smaller, lower entrance into an underground lake, which overflows in rainy seasons, creating an intermittent water flow called Petnica, flowing into Đetinja river. It is just over 1 km long. The cave's upper hall has lightened tourist trail, 555 m long, reachable by a circular staircase of 750 stairs. The "dry" hall contains stalactites and stalagmites, while the "wet" section is still geologically active, and is protected from outer atmosphere by an iron gate. It keeps the constant temperature of 9 °C , with high humidity. Largest hall in the still active section is called Cvijić's Hall, after the geographer Jovan Cvijić. A rare form of speleothems, helictites, developed in the cave. The speleothems are given jocular names: Single guy, Uncle Ljuba and his cats, Eagle on the rock, Snow White and the seven dwarfs. The cave is protected as the natural monument.

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