Except for the camera shutters clacking, you could have heard a surgical pin drop as the Army furled its seven unit colors and encased them in cloth bags at Walter Reed Army Medical Center on Wednesday.

The brass had spoken, and even Army Secretary John McHugh called it “a bittersweet moment, tinged in melancholy,” as the Army began its ceremonial closure of the venerable campus on Georgia Avenue on the 237th birthday of the Army Medical Corps.

Walter Reed Army Medical Center, 102 years old and showing its age, is closing and being merged with the expansive National Naval Medical Center in Bethesda and Fort Belvoir Community Hospital. The Bethesda facility will be renamed Walter Reed National Military Medical Center and will be run as a joint Army-Navy command.

The last patients from the Northwest Washington hospital will be moved Aug. 31. On Sept. 15, the Army will hand over the campus to the new tenants, the State Department and the District.

It’s hard to leave a place that’s so steeped in history, that’s been home for so long, and it’s harder still when you’re moving into the turf of a service rival.

“The Navy has the real estate, which is ironic given that they’re supposed to be out on ships somewhere,” McHugh said to laughter from the largely Army crowd. “But the Army’s got the people,” he added, to a lusty “Hooah!” from Army partisans.

The medical center’s staff of 6,000, including more than 600 Army physicians, treat 150,000 soldiers, other service members, retirees and family members in the Washington area each year. It’s also the Army’s leading center of clinical research and innovation.

“The ineffable culture of excellence, the love and care, the raw intelligence here . . . is not trapped in stones or mortar or steel,” said Lt. Gen. Eric Schoomaker, the Army’s surgeon general. “For me and the thousands I’m privileged to represent, I stand here with a heart burdened with sorrow yet swelling with pride.”

The center has had successes — the staff received the Army’s Superior Unit Award on Wednesday for its response in 2010 to the demands of treating patients and preparing for the closure. And it’s had its failures. In 2007, a Washington Post investigation found substandard living conditions for wounded troops in outpatient care and detailed the red tape they faced. The report resulted in a shake-up of the Army’s medical chain of command, millions of dollars in renovations at Walter Reed, a presidential commission on veterans issues, and renewed public awareness about the struggles of Iraq and Afghanistan veterans.

The hospital was named for the Army Medical Corps’s great hero, who entered the service just as scientists and physicians learned how germs infect the body and began to study bacteria. Reed was appointed to the board that determined how typhoid fever — which killed more soldiers than the Cubans during the Spanish-American War — was spread and how to prevent it. Not long after, Reed led another team that proved how yellow fever is transmitted, a major medical breakthrough. He died in 1902 of appendicitis.

His saber is one of the medical center’s most valued historical artifacts, and it was presented at the ceremony Wednesday to Rear Adm. Matthew Nathan, who will be the first commander of the new center. Maj. Gen. Carla G. Hawley-Bowland, head of the North Atlantic Regional Medical Command and Walter Reed Army Medical Center, who passed the sword to him, will retire Friday.

“The historical importance [of the casing ceremony] is it represents the integration of the two most prominent military icons in the world,” Nathan said. “It will allow us to have the synergy of two staffs together under one roof. Our plan is to provide care in a uniform manner . . . and it’s my challenge to preserve the traditions of each service in the joint format.”