These lush natural water potholes are believed to bring luck

 Bourke's Potholes are the primary natural wonder that attract visitors the world over. They're located in Blyde River Canyon Nature Reserve, in eastern Mpumalanga in South Africa. The potholes are found at the "confluence of the Treur and Blyde Rivers, on the reserve's western boundary." Thousands of year of natural geological carving has created these incredible cylinder-like potholes.

Sustained kolks in the Treur River's plunge pools have eroded a number of cylindrical potholes or giant's kettles, which can be viewed from the crags above. It was named after a local prospector, Tom Bourke, who predicted the presence of gold, though he found none himself. The pedestrian bridges connect the various overlooks of the potholes and the gorge downstream.

Wikipedia

Named after Tom Bourke, a gold prospector, who unfortunately never struck it rich. However, he did discover alluvial gold in the canyon during the latter part of the 19th century. After staking a claim, and panning for gold, he ultimately gave up, but he wasn't at a total loss, he discovered these natural potholes that are believed to bring luck. Though, it's weird cause Bourke wasn't actually lucky. But, oh well! Tourists have been visiting Blyde River Canyon Nature Reserve for years now, tossing coins in and using the potholes as a sort of "wishing well." 

National Geographic

When you visit you'll want to hit up Blyde River Canyon Lodge or Blyde River Wilderness Lodge, as both are perfect places to stay during your South African adventure.