Jeskyně Balcarka, Limestone cave in Ostrov u Macochy, Czech Republic

Balcarka Cave opens through a 6 m wide, 5 m high arched portal on the slope of Balcarova skála, from which a roughly 40 m corridor leads into two levels linked by domes and chimneys. Its largest space, the Great Dome, measures 65 m long, 15 to 25 m wide and up to 10 m high, and the Gallery on the upper level holds dense stalagmites, stalactites and stalagnates.

Josef Šamalík discovered the cave on 16 June 1923 after workers noticed a draft from a rock opening on Balcarova skála. In February 1924 he entered through a snow-filled sinkhole, and the cave opened to the public on Easter Sunday 1925. Šamalík explored it until his death in 1948; a full reconstruction closed it from 2007 to 2009.

The cave's dominant formation, the Handžár stalactite, is named for its curved shape resembling a Turkish sabre; it appears on the cave's emblem. The original was stolen during development work, so visitors now see a replica. The Popeluška chamber takes its name from the greyish tint of the limestone.

Tours typically last about one hour, and visitors should bring a light jacket since the cave maintains cool temperatures year-round. A parking area is located close to the cave entrance for easy access.

The dominant feature of the cave is the stalactite Handžár, curved like a Turkish sabre by a draught as dripping water deposited it; it appears in the cave's emblem. The original was stolen during the cave's opening-up works, so visitors now see a replica.