This museum functions as a supplement to the Smithsonian National Air and Space Museum (NASM) on the Mall. Udvar-Hazy  can be visited as a a side trip during a long layover at Dulles. Be aware that although admission is free (as it is to NASM), if you drive yourself the parking fee is a stiff $12. However, there is a bus from Dulles taking approximately 15 minutes to get there. It leaves every 45 min and costs 50 cents each way. There are lockers to store baggage at the airport, although they will only fit carry-on luggage.

     The museum is impressive in its size alone, covering more than 4 footbal fields with more than 120 planes. The museum highlights clearly are its SR-71 Blackbird, the bomber Enola Gay,  a Concorde, and the space shuttle Enterprise. All awesome to see and too large for the original Air and Space Museum. The museum is organized into commercial, space, warplanes, and history of aviation.As the NASM at the Mall is a little short on fighter planes, the warplanes on display at Udvar-Hazy are particularly well displayed and described. The space display is also very impressive.

      The overall layout of the museum is quite spacious, and provides both and overhead view (via catwalks) and an upclose view of almost all the planes. There is a guided tour that lasts approx 1.5 hours with guides explaining the intricacies of several notable planes. For engine buffs, a nice display of airplane engines throughout history is well done.

      If you are visiting Dulles and have the time, or are a real airplane buff ready for more after the NASM on the Mall, you should strongly consider  a visit to Udvar-Hazy. Its possible to also take a bus and It is a bit out of the way, but true airplane and space buffs will enjoy it, while those with a passing interest will have enough to see at the National Air and Space Museum at the mall.