You can learn a lot of interesting information from taking a tour of a medical institution. Check to see if Reston Hospital Center is open to the public while you are in the area.
Traveling on a budget? Reston Hospital Center is a good place to start your sightseeing in Reston. This health care institution is free. National Air and Space Museum Steven F. Udvar-Hazy Center, Wolf Trap National Park for the Performing Arts and Reston Town Center are close by and also worth visiting.