The Franklin Delano Roosevelt Memorial spreads along the Tidal Basin in a sequence of outdoor rooms, one for each of Roosevelt's four terms as president. It is less vertical and ceremonial than many Washington memorials: you walk through stone walls, bronze sculptures, carved quotations, and waterfalls that make the place feel unusually calm.
Come in the evening if you can. The water and low lighting soften the granite, and the memorial works well as part of a slow walk between the Martin Luther King Jr. Memorial and the Jefferson Memorial.