A $300 million, 177,000 square-foot museum dedicated to telling the story of the U.S. Army is being built at Fort Belvoir in Virginia, after nearly two centuries of preparation and a yearlong construction delay.

The museum, set to open in June 2015, got about $100 million from the Army, including the 41-acre site at Fort Belvoir, but its patrons must raise an additional $200 million. Sponsors have $63 million and need about $137 million more.