Top Five Worst Airports For Transit

1. London-Heathrow
If you have a connection through Heathrow, you need to expect long lines, long walks, possible bus rides, dank underground corridors invoking Dante's second circle of hell, passenger waiting areas with too few seats, and BAA's notoriously finicky security rules. Leave yourself plenty of time for a connection. Given that this airport handles much more volume than it was designed for, it's a wonder that it even manages to operate on a day-to-day basis.

2. Los Angeles
If you're transiting through this airport, chances are you're switching terminals, which means you either need to wait around for one of the infrequent shuttle busses (ten minutes or more) or just walk on your own. The terminals aren't exactly close. The airport may have been state of the art in the 1970's (or before) but it is showing its age today. The passport control and customs facilities are in these horribly depressing warehouse-like basement rooms. Lines at customs and security can be excessive if you arrive at the wrong time of day.

3. Philadelphia
If you're transiting through Philadelphia, chances are that you're on US Airways, which is bad enough as is. But Philadelphia's airport is ill-suited to be a major domestic and international hub. First off, it has only two runways capable of handling mainline jets, and with its riverside location, it is incapable of expansion. Even the smallest delay earlier in the day can magnify to result in twenty-deep takeoff queues. The terminal's gate areas are far to small, so the terminal ends up clogged with people at peak times. Plus, the airport consists of seven piers jutting out from a linear concourse, which can make for some mightily long walks if you need to switch planes. Also, the baggage handling at this airport is arguably the worst in the country.

4. Paris-Charles de Gaulle
CDG Airport has two main terminals that are not particularly close to one another. Get ready for a bus ride. Upon further review, however, Terminal 2 is actually made up of six mini-terminals, each of which has its own security checkpoints and passport control areas. Unless you're lucky enough to connect within the same pod, you need to exit the airside area and undergo all the formalities to get to your next plane. Signage is not great and customer service is downright bad. You can be mere feet from your departure gate but an hour away from boarding your plane.

5. Dallas/Ft. Worth
DFW airport consists of five terminals, four of which are semi-circular with gates around the perimeter of the circles and an access road inside. With multiple ticket counters and security checkpoints, DFW is great if you're catching a flight, since you can be dropped off very close to where your gate happens to be. If you're connecting, however, you have no such luck. You need to walk all along the perimeter of the terminal, passing by each and every gate along the way, to even reach the point where you can switch to another terminal. An airport train system helps cut down on the ordeal, but waiting for a train is the last thing you want to be doing when time is running short.

Dishonorable Mention: Washington-Dulles
Dulles' gate areas are found in one of two horizontal concourses, physically separated from the ticket counters and security checkpoints, or in a small zone attached to that main terminal building. If your flight parks at one end of the C/D Concourse and your connection departs from the other end, you have a long walk in a straight line to get there. Moving walkways would be very helpful, so naturally, there aren't any (save one oft-broken exception). If you need to change concourses, you must wait for one of the mobile lounges that look like moon buggies to take you there. They run on their schedule, not yours. Passengers clearing customs and connecting to other flights proceed through the midfield inspection facility, where CBP staff always seems completely unprepared for the surge of arrivals mid-afternoon.