Boybuloq Cave
The cave is the deepest known cave in Asia having been explored to a depth of from the entrance. At the lowest discovered level a water-filled siphon blocks further exploration. It is thought that the cave has the potential to be the deepest known cave in the world, with a theorised depth of making it deeper than the Veryovkina Cave. The explored length of the cave is .
Lazareva Pećina
The Lazareva Pećina, which translates Lazar's Cave, is the longest explored cave in Serbia. Located in Bor municipality, near Zlot, the cave is also sometimes referred to as Zlotska Cave. According to 2012's "Recent Landform Evolution: The Carpatho-Balkan-Dinaric Region", the cave is long. The cave is situated near the entrance of the deep canyon carved into the mountains by the river Zlotska.