The Cave of Perama, about 5 km north of central Ioannina, is one of the largest and most heavily decorated stalactite caves in Greece. The 1,100-metre developed route takes about 45 minutes and passes through 19 separate chambers — narrow corridors, vast halls, columns, curtains, and oddly shaped speleothems lit by the cave's own colour scheme.
Tours run hourly (guided in Greek with English summaries). The temperature inside is a constant 17°C, so bring a layer even on the hottest summer day. A small fossil collection at the entrance includes cave-bear remains found during the excavations.