VALLEYS
   The present-day mountain relief in Central Balkan National Park is the product of mighty geological processes, refined over millennia by water and wind. Rounded ridges and high peaks alternate with deep canyons, vertical rock faces and caves.
   The Balkan Range is the central structural mountain strip in the Balkan Peninsula. It is made up of several basic types of rock, most commonly southern Bulgarian granites, sandstone, crystalline schists, etc. At altitudes over 1,800 meters above sea level there is some evidence of glacier activity in the geological past.