One of Washington’s best-kept secrets, The Brewmaster’s Castle is the most intact late-Victorian home in the country, and a Landmark on the National Register of Historic Places. Built in 1892-1894 of poured concrete and reinforced steel by German immigrant, local brewer and philanthropist, Christian Heurich, it is also the city’s first fireproof home. Heurich was Washington’s second largest landowner, the largest private employer in the nation’s capital, and as the world’s oldest brewer, ran his brewery until his death at 102.
It is maintained by a private foundation and a dedicated director lives on site. The house is large, but the tours have an ‘initmate’ feel. You can schedule a private tour on a Wednesday or walk-in at their scheduled times Thursday, Friday or Saturday (11:30 and 1 each day, with an added 2:30 tour on Saturday).
For years I drove past this mansion (located at the intersection of 20th and New Hampshire in northwest DC) on the way to my hotel in Georgetown and never knew what it was. Finally this summer I planned a visit. It is within easy walking distance of Dupont Circle.  If you enjoy historic homes, this is a real treat. The history is fascinating, including romance and tragedy. The local DC brewery was located at the site of the John F. Kennedy Center for the Performing Arts (another gem, but not hidden). A blog post on the brewery has some interesting anecdotes. And a little bit about the beer can be found at Foggy Bottom.com .