Lake Voulismeni (Gr: Λίμνη Βουλισμένη) or just "the Lake" for the locals, is located at the centre of the town of Agios Nikolaos. It has a circular shape of a diameter of 137 m and depth 64 m. The lake connects to the harbour of the town by a channel dug in 1870.
A panoramic view of the lake can be seen from a small park situated above it. According to legend, the goddess Athena bathed in it. Every year at midnight turning to Orthodox Christian Easter day, the majority of the population of the town gathers around the lake to celebrate with fireworks, and firecrackers.
It was reported that the German army during their withdrawal from the area at WW2, disposed parts of their weaponry and/or vehicles into the deep lake.
A local urban legend has it that the lake is bottomless. That notion is potentially based on its impressively disproportional high depth compared to its width (64m depth on only 134m width) or/and on locals noticing disturbances at the surface or also the level of the water during the Santorini (Thera) earthquake of 1956. Because of the latter, many assume a possible geological relation of the two locations, but this claim has not been substantiated by known scientific surveys to date.

Near the beautiful village of Vrahasi there is the imposing gorge of Selinari, formed by the mountain of Anavlohos (625 m) to the north and the mountain Fonias o Detis (818 m) to the south. The symbol of Crete, the Cretan wild goat (Agrimi or kri-kri) and the Griffon Vulture are two rare species that used to reside in the gorge. The authorities in Vrahasi intend to establish a center of protection of the local fauna and flora at the gorge of Selinari and to develop a wildlife station, to provide observation of the Griffon Vulture colony at the east side of the gorge of Selinari. The hunting is forbidden in an area covering 10 sq.km. around the gorge.