The Watergate hotel is old. Its cement is faded, and the only retail in sight is an old gas station on an awkward corner. The mid-century modernism, once thought glamorous, feels as aged and isolated as the neighborhood itself. Pull into the small circle in front of the luxury hotel, however, and a valet will rush to your door, asking if you’re checking in or just stopping by. In June 1972, the neighborhood was newly revitalized and prestigious.