One tenth of Slovenia's territory is protected under nature conservation laws. The first natural park in Slovenia was established in 1888 – the forests of Kočevje are the only preserved primeval woodland in Europe. 

The Triglav National Park, at 83,807 hectares, is the biggest Slovenian park. It was named after Slovenia's highest summit, Triglav (2,864 m). Three regional parks (Kozjansko, Notranjska and Škocjan Caves) and 44 landscape parks are intended for the protection of heritage and diversified landscape, forests and native plant and animal species. 

Valuable natural features also include one of the deepest caves in the world (Čehi II), the stunning intermittent lake (Lake Cerknica) and a UNESCO World Heritage site (Škocjan Caves).