This region is also home to one of the most important single geological features in the Czech Republic, the Macocha Abyss, a gorge 138 m deep, which was formed when the ceiling of an underground cave chamber collapsed. Macocha Abyss is also the place where the Punkva River begins to run underground through the Punkva cave system, and two small pools of water are visible at the surface. The Moravian Karst is a popular tourist attraction in the local area, and large numbers of tourists visit in the summer months. In addition to caverns, the nature preserve also contains well-marked bicycle trails and hiking paths to explore.