The story of gold is told in a bus tour taking in the site where Harrison identified the gold reef in Langlaagte.
The reef mines sank far underground, and used expensive machinery and complex metallurgical processes to separate the gold from the waste rock.
In the short term, I think we're just going to have to reef in the sails and hold on tight.
In its pomp KGF was the wealthiest gold reef in the British Empire, with the deepest shaft at Champion Reef.
I can raise and strike a sail, reef it and stow it.
Instead, it really does consist of a large number of small reefs, in fact if you look at a map in the museum behind us you'd see very clearly that it's not one continuous solid reef .
Early on, the wind filled to 18 knots and the yachts were forced to reef their mainsails and change headsails under difficult conditions.
The technique was to go slowly back and forth parallel to the shore on the basalt reef and locate any fissure veins containing copper or other minerals.
Then there is the historical aspect of the reef, which brings into focus the reef as resource, a story of commodities and extractive industries, from fishing to mining.
After the alluvial gold had been mined, companies were formed to start reef mining.