When you book a flight to Denver, Colorado, you can anticipate great things. Your trip in the Mile High City begins the moment you land at Denver International Airport, the country's busiest airport. Denver International Airport is one of the most architecturally impressive airports in the United States, with a large rotating art show. You can even do a little last-minute travel shopping—from the Tattered Cover to Taspen’s Organics, Denver International Airport’s shopping scene is worth…