It’s an amazing story: A forgotten downtown building is slated for demolition, but turns out to be a time capsule of late 19th-century Washington. There is no indoor plumbing, gas lamps are evident, and remnants of the original wallpaper are visible in the gloom. Even more surprising, letters and signs discovered in the attic show the building was the site of Clara Barton’s Missing Soldiers Office.

Barton lived here during and immediately after the Civil War. She also used the property to store the supplies she received for her work on the battlefield, and in 1865 turned it into the “Office of Correspondence with the Friends of the Missing Men of the United States Army.” By the time the office closed in 1867, she and her staff had responded to more than 63,000 letters from grieving parents, family, and friends whose sons, brothers, and neighbors were missing. Their work identified the fate of more than 22,000 men.

Learn more about Barton’s remarkable life and work and the rediscovery and restoration of her office, set to open as a museum, from George Wunderlich, executive director of the National Museum of Civil War Medicine in Frederick, Maryland. Participants have the opportunity to sign up for one of four private tours* of the not-quite-yet-open-to-the-public Clara Barton’s Missing Soldiers Office.

Participants can select a tour at 10 a.m. or 1 p.m. on Thurs., July 17 or 10 a.m. or 1 p.m. on Sat., July 19 (4 options available).