Jaskinia Wielka Śnieżna

Jaskinia Wielka Śnieżna ("great snowy cave") is a limestone cave system in Mount Małołączniak in the Western Tatra Mountains, of the Carpathian Mountains System, in southern Poland.

With the length of 23.723 kilometres (14.741 mi), and vertical range of 824 metres (2,703 ft), it is the longest, largest, and deepest cave in Poland.

[2] Wielka Śnieżna has five entrances: They are connected by a complicated system of shafts and passages.

Exploration in the 1960s bottomed out at a sump or siphon, a U-shaped tunnel filled with water, at a depth of 752 m (2,467 ft).

In 1972, cavers using scuba diving gear were able to push past the sump for the first time.