Kimberley is famous for the Big Hole, which is often called the worlds deepest man made hole. Kimberley is the place where diamonds are found. And the Big Hole is a huge pit, almost circular and 215m deep, right in the middle of the town.
The diamonds found here were formed in vertical pipes. Huge layers of rocks eroded, and so it is cut through by today's surface. The circular pipe reaches the surface right on the farm, two Dutch settlers bought in 1871. The two brothers called Johannes Nicolaas and Diederik Arnoldus de Beer soon discovered the diamonds on their ground. This lead to a diamond rush, which made it impossible for them to keep the land. They were not able to protect it from the growing tide of intruders, so they sold it. And although they did not become the owners of the mines, one of the mines inherited their name and until today the diamond trade is connected with their names. De Beers is the company which today controls virtually all diamonds on Earth.
But back to history. First two big mines formed, the De Beers and Kimberley mines. Cecil John Rhodes and Charles Rudd gained control of both mines and merged them, forming De Beers Consolidated Mines Limited in 1888.
In the first time the diamonds were mined in an opencast mine, following the pipe. Colesberg Kopje soon disappeared and turned into a pit. The result was the Big Hole, a vast crater dug entirely with picks and shovels. In this opencast 2,722kg of diamonds were mined until it closed in 1914. It is the largest hand-dug excavation in the world.
Today the Big Hole is about 215m deep, but 40m of ground water leave only 175m visible. Originally the hole was 240m deep, but after it was abandoned it was used to throw debris in. The underground Kimberly Mine was mined to a depth of 1097m.
The Kimberley Mine Museum is located at the rim of this hole, and is an open air museum, a small village showing the history of diamond mining at Kimberley. A complete little diamond rush town with shops and houses, a church, diggers' tavern, Barney Barnato's Boxing Academy, and the De Beers directors' private railway coach. The Transport Hall contains an assortment of late 19-century vehicles. An exhibition at De Beers Hall displays uncut diamonds and jewelry. On display is the largest uncut diamond in the world, the "616". Its name is its weight: 616 carats. Even better known because of its history is the "Eureka", the first diamond discovered in South Africa.
In 2006 De Beers invested R50 million (about USD 7.7 million) for the renovation of the Big Hole heritage site. The museum is modernized, with an audiovisual theatre and a cantilevered platform above the rim of the Big Hole that allows visitors a vertical view down into the hole, as its end is across the rim.