Bourke's Luck Potholes

Bourke's Luck Potholes are a series of cylindrical rock potholes carved into yellow quartzite and dolomite at the confluence of the Treur and Blyde Rivers, at the northern end of the Blyde River Canyon in Mpumalanga, South Africa. The potholes formed through a natural erosional process in which small pebbles and gravel carried by fast-flowing floodwater became trapped in minor depressions in the riverbed, and the churning, swirling motion of the trapped material, driven by the current, ground the depressions ever deeper and rounder over thousands of years, in the manner of a natural drill. The site takes its name from a nineteenth century gold prospector, Tom Bourke, who staked a claim nearby, and the smooth, water-sculpted bowls and cylindrical shafts remain in active formation wherever floodwater and loose rock continue to interact with the riverbed.