Then vs. Now: In 1864, Arlington House and 200 surrounding acres became a Union military cemetery. Today, more than 400,000 people have been buried throughout Arlington National Cemetery’s expanded 624 acres. In 1921, an unknown soldier from WWI was interred at Arlington to honor service members whose remains were never identified. Unknown soldiers from WWII, Korea and Vietnam were also laid to rest in an expanded memorial. The remains of the Vietnam unknown soldier were identified in 1998, and his former crypt remains vacant. 📸Getty Images/Library of Congress #MemorialDay #MemorialDayWeekend #MemorialDay2019 #MDW #Arlington #WashingtonDC #Washington #DC #news #cnn #cnnpolitics #us #ushistory