Oshikoto Region

Namibia

Lake Guinas is the larger of only two natural lakes in Namibia. It is a sinkhole lake, created by a collapsing karst cave located 32 km north of Tsumeb near the D3043 road.

Lake Guinas is home to Tilapia guinasana, a mouth-breeding species of fish that was endemic to this lake. It has later been introduced to Guinas' sister lake, Lake Otjikoto, as well as into few farm dams nearby.[2] The claim that lake Guinas is indeed connected to lake Otjikoto by underground caves is frequently made but not proven as yet.

The lake is situated on private farmland but can be visited with the permission of the owner. Source: Wikipedia.org.

Private lake (sink hole). Very difficult dive site access.