I'VE been to some bizarre tourist attractions in my time, and having been born and raised in County Durham's mining belt, I've also seen some pretty big holes. So when I arrived in Kimberley on Friday night to be greeted with a sign that read 'Kimberley – home of the Big Hole', my Saturday morning sightseeing was sorted straight away.

What can you say about the Big Hole? Well, firstly, it's big. And secondly, it's a hole. Thank you, good evening and feel free to browse the Big Hole memorabilia on the way back out.

Actually, that's being a bit unfair on an attraction that, while hardly the greatest thing you're ever going to see in your life, is an integral part of South Africa's colonial history. And having spent the best part of three days in the rest of Kimberley, the competition for something to do for a few hours is hardly intense.

The Big Hole is the largest man-made hole anywhere in the world. It's 500 metres wide and almost 250 metres deep, and the entire thing was excavated by pickaxe and shovel.

Why? Because the rock that was dug out of it contained diamonds, and Kimberley's history is intrinsically bound up in the discovery and exploitation of the richest diamond field in Africa.

The first diamond was discovered in 1866 and five years later, a number of gems were discovered at a farm owned by Johannes Nicolas and Diederick Arnoldus De Beer.

The De Beers sold their farm, which had previously been valued at £50, to prospectors for the sum of £6,300. It became the focal point for a diamond rush that drew in speculators from all corners of the world.

One was an 18-year-old Oxford University graduate named Cecil Rhodes, who went on to control 90 per cent of the world's diamond production and drew a number of nations including Zimbabwe and Zambia into the tentacles of the British Empire.

He spent most of his days in Kimberley – one of the town's most popular pubs, the Halfway House, still boasts a saloon area where he would be served beer while still in the saddle of his horse (the world's first ride-through?) - and helped found the De Beers Mining Company, a unified conglomerate that would go on to become one of the most powerful business forces in the whole of Africa.

Today, most of his legacy lies elsewhere, most notably in modern-day Zimbabwe, which was formerly known as Rhodesia.

Run-down Kimberley is not a town that looks as though it was once at the heart of his business and political empire. It was though, and one giant clue remains. A bloody big hole.