The Lake of Agios Nikolaos, also known as Voulismeni or Vromolimni, is located in the center of Agios Nikolaos, being the trademark of the city, with a total perimeter of 500m. A walk around the picturesque lake is a very nice experience, although human interventions have altered much of its initial form. Concrete piers have been built in a section around the lake, where small boats are moored, while in some places columns have been placed from the ancient town Lato pros Kamara, which was located here. The boats have access to the sea through a shallow canal 60m long and 12m wide, which was opened in 1870.
Dozens of legends are associated with the lake due to its very deep waters, such as the fact that it has no depth. Nevertheless, Voulismeni is an ordinary karstic dolin with its maximum depth at 48m depth. The salinity of the lake decreases with depth, which means that fresh water gushes from the bottom. Prior to the canal's opening, the lake was referred to as freshwater. Unfortunately, water today is heavily polluted by high concentrations of hydrocarbons (mainly from boat fuels) and nitrogen / phosphate compounds. At the bottom of the lake, the Germans had disposed military equipment before leaving Crete in 1944.
In recent years, cliff diving contest have been held on the lake. Indeed, the west side of Voulismeni is suitable, as a steep cliff of 20m is created from where the athletes jump.