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. The cave is within Tatra National Park. With the length of 23.723 km, and vertical range of 824 m, it is the longest, largest, and deepest cave in Poland.

Morphology

Wielka Śnieżna has five entrances: They are connected by a complicated system of shafts and passages. Several of them contain underground trickles, waterfalls, pools, or siphons. The cave is drained by a karst spring known as Lodowe Źródło ("icy spring").

Exploration

Jaskinia Śnieżna was discovered in 1959 by cavers from Zakopane. In 1960, it was explored to a depth of 545 m, which made it, at that time, the fourth-deepest cave in the world. In the subsequent years, the cave was intensively explored and connected with other caves. Exploration in the 1960s bottomed out at a sump or siphon, a U-shaped tunnel filled with water, at a depth of 752 m. In 1972, cavers using scuba diving gear were able to push past the sump for the first time. Their exploration pushed down to a depth of 783 m. Subsequent efforts have found the cave to be 824 m deep. Exploration of the cave is still ongoing, including attempts to connect the cave to Śnieżna Studnia, second-largest cave in Poland.