Rak is a creek in Inner Carniola, a traditional region of southeastern Slovenia. It sources in Zelše Caves (Zelške jame) to the west of the village of Zelše, flows across the Rakov Škocjan karst valley for 2 kilometres (1.2 mi) and enters Weaver's Cave (Slovene: Tkalca jama), where it continues for 3 kilometres (1.9 mi) and merges in Planina Cave (Planinska jama), above 300 metres (980 ft) from its entrance, with the Pivka River to form the Unica.