The U.S. has more than its share of big airports. America's large domestic travel market has allowed several carriers to build up big hub operations that drive high passenger traffic numbers. Delta Air Lines (NYSE:DAL) and American Airlines (NASDAQ:AAL) have the biggest hubs in the U.S. airline industry -- and not surprisingly, these are among the 10 busiest airline hubs in the world.

However, Delta Air Lines and American Airlines aren't the only airlines carrying lots of traffic through big hubs. Indeed, as of last year, six of the 10 busiest airports in the world were outside the U.S.

Check out which airports made the top 10 list for 2013 in the slideshow below! Then let me know if you've flown through any of these airports, and whether you had a good experience there.