Ever wonder what kind of shoes Steve McQueen wore in The Great Escape?
According to a booklet that comes with the shoes, they are Clark's Desert Boots. McQueen wore them off-screen occasionally (as seen in the photo below.).

These shoes are still being made and are available at amazon.com! To see them, click on the following link:
Men's Clarks England Desert Boot
(Thank you to Paul Dezentjé for the information!)