Kozjak is a left tributary of the Soča river. Its springs are getting water from the high mountains from Oblo brdo (1957m), Krnicica (2142m) and Srednji vrh (1957m).
There are six waterfalls but only lower two are accessible by the well tourist route. Waterfall Veliki Kozjak is very picturesque. Brook has caved a nature hall which looks like a karst cave. It falls in a dark-green pool.
ACCESS: From Kobarid over the Napoleon Bridge in the direction to Drežnica. After 150 m follows a left turn to the remains from WWI and to Veliki Kozjak. The hike from Kobarid takes less than 60 min.