Due to the exceptional aesthetic value of its natural and ethnological heritage, the source of the river Grab and the upper part of the river with the famous mills, with a total area of 0.39 km2, was protected as important landscape. The source of this river, which is only 2 km long, is accessed by the trail on the right bank, which passes along well-preserved and functional mills and a beautiful stone bridge, and then enters a short canyon and breaks through hornbeam woods with some oaks, willows and poplars. The river branches off soon after and forms ponds whose playfulness is enhanced by several small waterfalls.
The source’s fauna consists of a dozen species of birds: owls, ravens and kestrels prefer the cliffs of the canyon, blackbirds, orioles, goldfinches and warblers opt for the woods, and dippers and snipes live near the water. The herpetofauna also accommodates a dozen species: snakes (horned vipers, grass snakes, dice snakes and the Bakan whip snakes), lizards, and amphibians (green frogs, tree frogs, spotted salamanders and the endemic olm which sometimes floods out of its underground habitat).
Source: TZ Trilj