Kef Toghobeit Cave
Kef Toghobeit is a karst cave near the settlement of Bab Taza in Chefchaouen Province, Tanger-Tetouan-Al Hoceima, in northern Morocco. Currently known to be long and deep, it is the deepest cave in Morocco, and the third deepest cave in Africa.
Although Kef Toghobeit has been well-explored, its full extent is not yet known. Indeed, the karst topography of the Rif mountain range where the cave begins has barely been mapped - just 1000 caves are known in Morocco, and the geology would suggest that more than this exist.
Hranice Abyss
The Hranice Abyss (), the English name adopted by the local tourist authorities, is the deepest flooded pit cave in the world. It is a karst sinkhole located near the town of Hranice (Přerov District). The greatest confirmed depth (as of 27 September 2016) is 473 m (404 m under the water level), which makes it the deepest known underwater cave in the world. Moreover, the expected depth is 800–1200 m.