Building on the enormous popularity of the Air and Space Museum and needing more room to showcase its largest aircraft, including a Space Shuttle, the Smithsonian opened the National Air and Space Museum Steven F. Udvar-Hazy Center (14390 Air & Space Museum Parkway, Chantilly, Va., 703/572-4118, www.nasm.si.edu , daily 10 a.m.-5 p.m., admission free, parking $15) in 2003, adjacent to Dulles International Airport.
The holdings at the main National Air and Space Museum in DC  and the Udvar-Hazy Center represent the largest collection of aviation and space artifacts in the world.
In addition to housing some of the world’s most important historic and groundbreaking aircraft, including the Enola Gay, a Concorde, and an SR-71 Blackbird, the three-story center has an IMAX theater, a mock aircraft control tower featuring the real-time voices of Dulles controllers, and in late 2011, a hangar where visitors can watch the work of museum restorers.
Directly across historic Route 28 from the Udvar-Hazy Center is the Sully Plantation (3650 Historic Sully Way, Chantilly, Va., 703/437-1794, www.fairfaxcounty.gov/parks/sully/ , Wed.-Mon. 11 a.m.-p.m., closed federal holidays, tours $7 adults, $6 students, $5 over age 64, $5 ages 5-15), built in 1799 by Richard Bland Lee, Virginia’s first member of Congress. The Federal- and Georgian-style manor home and its grounds have been preserved by Fairfax County to showcase early-19th-century life in Virginia.
Preservationists will enjoy learning about how the site was spared during the construction of Dulles airport, and the grounds, with preserved outbuildings and a representational slave quarters, indicate how the Lee family lived during the early days of the nation.