Namibia is very well known for its diamonds and as a result, most of its coastline is closed for diving. The other big factor to consider is that most of its coast is also desert, which makes it inaccessible or very difficult to reach. However there are still some sites for diving, including lakes, sinkholes and cave lakes, especially for someone who loves challenges. Such as Harasib, a cave lake with a known water depth of about 265 meters, this underground lake is about 100 meters below the surface and proficiency in vertical caving techniques is required to reach the water.