One interesting historical real estate fact about Northwest Washington, D.C. is that the area was once home to a large number of embassies and diplomatic missions. Many of the city's grandest mansions and stately homes were built in the late 19th and early 20th centuries and were used as embassies and diplomatic residences. The neighborhood is also home to a number of important cultural institutions, including the National Zoo, the National Cathedral, and the Smithsonian's National Museum of American History. In recent years, Northwest D.C. has become a popular destination for young professionals and families, drawn to its tree-lined streets, spacious homes, and proximity to downtown. The neighborhood is also home to a number of vibrant commercial districts, including Dupont Circle, Adams Morgan, and U Street.