The Wonderful Rocks or Wonderful Bridges are a natural phenomenon in the Rhodope Mountains. They are located in the karst river valley of Erkyupriya in the Western Rhodopes. They stand at the foot of the Big Persenk Peak, 1,450 meters above sea level. The turbulent waters of the river have, at some point in the past, collapsed a cave that was in this place, forming these huge marble bridges.
Asmall path from the road leads to the remains of the cave. The largest bridge is about 15 meters wide and 100 meters long. It is decorated with three arches, the largest of which is 45 meters tall and 40 meters wide. A smaller bridge is located 200 meters downstream. The last bridge is where the river ends, its waters reappearing on the surface three kilometers further.
There are many local legends about the creation of the Wonderful Rocks. The most common one tells of the appearance of a dragon. Long ago in the nearby village of Zabardo there were many large herds of sheep, which attracted the dragon. For many years the village shepherds suffered from the attacks of the dragon, before they found a way to get rid of him. The villagers loaded up a donkey with tinder, lit him on fire and sent him towards the dragon. He swallowed it without hesitation. Desperately he tried to escape and hid in a small hole in the ground, which opened wider due to his huge body. After many years, his body rotted away and his bones left the huge arched bridges.