Hranická propast (CSAK KUTATÁS / research only)
Diving is prohibited for the public: only authorised research teams dive here. The Hranice Abyss on the right bank of the Bečva river is the deepest known flooded freshwater cave in the world. The dry part is 69.5 m deep and the flooded part has been measured to 450 m by ROV in 2022 without reaching the bottom, a total of more than 519.5 m. A 2020 study suggests the flooded shaft could reach about 1 km. The site lies in the Hůrka u Hranic national nature reserve; the dry abyss can be viewed from a fenced platform.
Tiefe: 0–450 m