The largest US flag, dubbed "Superflag," was once displayed at Hoover Dam.
May 1, 1996, a 505 x 255 foot American Flag was flown from the downstream face of Hoover Dam. The flag weighed 3,000 pounds and was hoisted by 3 separate cables located at the top of the Dam. The flag was part of a ceremony in which the 1996 Summer Olympic torch was carrried across Hoover Dam.
Happy Fourth of July Independence Day!