Colorado Casino digs in

More than 611,640 cu m of granite have been dug out of a Colorado mountainside to make room for a casino-hotel development that will take at least seven years to build and could cost as much as $US1 billion.

The first $US160 million phase of the Black Hawk Casino by Hyatt will be the gambling casino, and the second phase will include the hotel.

There will eventually be two casinos at ground level and two hotels connected by overhead walkways.