Udachnaya Pipe from the air, taken by Alexander Stepanov

This is one of the largest man-made holes in the world, a diamond mine deep in the reaches of Siberian Russia. It is about 600 meters deep (that’s over 1800 feet for the American folks). The top layer of the hole is about a mile across, and a little over half a mile wide.

According to the Wikipedia article, the open-air mining will cease around 2010, and operations will shift into an underground manner. A few of the research papers devoted to this mine state that diamonds are probably still available to a depth of about 1000 meters or so.

The settlement near the mine is named after it (Udachny), and also feels local weather patterns because of being next to this giant hole.

You can see this mine for yourself via Google Maps.