Took 40 minutes of fairly pretty driving from Washington to Chantilly and it was completely worth it. I should mention, it's also do-able by public transit too. My original reason to go was to see an old IMAX movie I saw 30 years earlier (The Dream Is Alive). That was a fantastic memory for me, and a genuine pleasure to be able to see it on Virginia's largest screen. The first thing you see when you walk into the main hanger area are the SR71 Blackbird and the Space Shuttle Discovery lined up right before you. I was only able to spend about 2 hours there, but you could easily spend twice that amount of time and really enjoy. They have everything from the Concorde to the Enola Gay. The Air & Space Museum back at the Washington Mall is a great warm-up or tease for this place.