Gates and Buffett tour Alberta oil sands

Two of the world's richest men have made a surprise visit to Alberta's oil sands.

The Globe and Mail reports Microsoft Corp. founder Bill Gates and Warren Buffett of the holding company Berkshire Hathaway got a tour Monday to learn about development in the region.

Canadian Natural Resources, Canada's second-largest oil and gas firm, hosted part of the tour at its $9.3 billion Horizon oil sands project, which is under development.

Greg Stringham, vice president at the Canadian Association of Petroleum Producers, says Gates and Buffett wanted a general overview of the oil sands and information on Canada's position in the energy world.