Chantilly is a census-designated place (CDP) located in western Fairfax County of Northern Virginia. Recognized by the U.S. Census Bureau as a census-designated place (CDP), the community population was 23,039 as of the 2010 censusdown from 41,041 in 2000, due to the splitting off of parts of it to form new CDPs including Greenbriar and Fair Lakes. It is named after an early 19th-century mansion and farm. Chantilly is part of the Washington metropolitan area and is approximately 24 miles (39km) from Washington, D.C. Chantilly is home to the Steven F. Udvar-Hazy Center annex of the National Air and Space Museum and the headquarters of the National Reconnaissance Office. Chantilly was also home to the annual Bilderberg summit in 2002, 2008 and 2012.