The Wonderful Bridges, also known as “Skalnite mostove” (the “Rock Bridges”), are a natural phenomenon in the Western Rhodopes, situated at the karst valley of the Erkyupriya River. The largest and most impressive bridge is about 15 meters wide and almost 100 meters long. Its highest arch is 45m high and 40m long. The other bridge is remote and the access to it is a bit more difficult. Next, there’s the third bridge - a cavern that literally “devours” River Erkyupriya’s waters and it emerges back to surface, three kilometers further down. In the past, these bridges had actually been an entire cave, formed under the rifting activities of the waters. In time, parts of it were gradually collapsing, thus creating the majestic marble bridges.