A small but exceptionally diverse natural area, home to interesting biodiversity as well as unusual rocks, rivers flowing through small canyons, picturesque waterfalls and wooden bridges. It was designated for the protection of oak forests, riparian willow formations and mixed ash-alder groups along the rivers.
Protected animal species include tree frog, Balkan spadefoot toad, yellow-bellied toad, Aesculapian snake and blotched snake, javelin sand boa, European pond tortoise, Hermann's tortoise and spur-thighed tortoise. Notable bird species for observation include black stork, short-toed snake eagle, Levant sparrowhawk, Eurasian sparrowhawk, Eurasian goshawk, booted eagle, short-toed snake eagle, lesser spotted eagle, long-legged buzzard, honey buzzard, black kite, peregrine falcon, hobby falcon, Eurasian eagle-owl and stone curlew. Defiletoto is also home to the marbled polecat and the otter. In open areas there are colonies of European ground squirrel.