Chudnite Mostove (The Wonderful Bridges) is a rock phenomenon also known as the Skalnite Mostove (The Rock Bridges). It is situated in the karst valley of the river Erkyupriya in the West Rhodope mountain on 1450 above the sea level. In the past the bridges had been one entire cave. Parts of it were collapsing with time, forming majestic marble bridges. The large bridge is about 15 meters wide in its wider parts and almost 100 meters long. It consists of three arches. The small bridge is at a distance of 200 meters from the large one along the river current. It is impassable, 60 meters long, with total height of 50 meters, and the height of the arch is 30 meters. There is also a really small third bridge after it, which is a ponor cave, in which the waters of Erkyupriya river disappear, to appear again on the surface 3 kilometers farther. The two large bridges are safeguarded and accommodated for the touristic needs. Passing is allowed over and under them. An option for accommodation is offered by the huts situated in close proximity to the sites.