The Trigrad Gorge is a majestic 7km gorge that has been carved into the marble rocks north of the Rhodopean village of Trigrad by the Trigradska River for millions of years. In some places, the distance between the two slopes is 300m, but in the main part of the gorge, which is 2-3km long, they are only 100m from each other. On the west side, the height of the vertical rocks is 180m, and on the east side they reach 300-350m. These huge dimensions make it the third-largest gorge in Bulgaria.