Škocjan was inscribed on the UNESCO World Heritage List in 1986, and the Martel Chamber inside it is among the largest discovered underground chambers in Europe. Where Postojna is decorative — formations, a train, high throughput — Škocjan is structural: the Reka river runs through a canyon 146 m deep, and the walk crosses it on a bridge. There are stairs and a substantial walk, so it suits mobility less well than Postojna. Most visitors who see both prefer this one.
