title: Benjamin Henry Latrobe
context: Latrobe continued to design houses after he emigrated to the United States, mostly using Greek Revival designs. Four houses still stand that Latrobe designed: the Decatur House in Washington, D.C.; Adena in Chillicothe, Ohio; the Pope Villa in Lexington, Kentucky; and the Sedgeley Porter's house in Philadelphia. As one of Latrobe's most avant-garde designs, the Pope Villa has national significance for its unique design. He also introduced Gothic Revival architecture to the United States with the design of Sedgeley.[84] The mansion was built in 1799 and demolished in 1857; however, the stone Porter's house at Sedgeley remains as his only extant building in Philadelphia.[85] A theme seen in many of Latrobe's designs is plans with squarish-dimensions and a central, multi-story hall with a cupola to provide lighting, which was contrary to the popular trend of the time of building houses with long narrow plans.[86]
question: How many buildings in Washington D.C. are designed by Latrobe?
answers: Four