Like Slovenia's best known cave system, Postojna, the Babji Zob (or Hag's Tooth) caves became popular with visitors in the 19th century. Although much smaller than its bigger sister, there are some impressive stalactite formations here, as well as spiral stalactites and calcite crystals. Accessible for the inexperienced and spontaneous; there are arranged paths, electric lights, and it's open for all from May to August. Just turn up at 10:00 on Sunday morning, if you make it out of bed. Otherwise give the folks at the Society for Cave Research (Društvo za Raziskovanje Jam) a call and arrange your visit. The cave entrance is located above the villages of Bohinjska Bela and Kupljenik (about 6km from Bled).