Heathrow Airport

Heathrow Airport in London, Europe's busiest hub, has been a bottleneck for travelers all summer with flight delays and misplaced baggage among the biggest complaints.

Now Heathrow's Terminal 5, slated to open March 27, is supposed to alleviate some of the congestion by handling 30 million passengers a year.

A baggage claim area, shown here, in the new terminal.