Moravian Karst, karst in Jihomoravský kraj (region), eastern Czech Republic. It is a limestone area containing a labyrinth of swallow holes, underground passages and lakes, caverns, and calcareous formations. One of several small, disconnected karst areas, it is situated north of Brno, along the eastern bank of the Svitava River, and eastward along the latter’s underground tributaries, the Punkva and the Říčka. In area the karst extends for about 20 miles (32 km) north-south and 6–9 miles (10–15 km) east-west.