Martin Luther King Jr. Memorial Library

The main premises of DC’s public library system contains the third-floor Washingtoniana Room, where extraordinary reference librarians help researchers sort through books, historical directories, photographs, maps, archival collections from 150 individuals and organisations, and more than 13 million newspaper clippings concerning the District of Columbia and vicinity. Designed by Mies van der Rohe in steel, brick and glass, and built in 1972, the library is one of DC’s few modernist buildings. It was listed on the National Register of Historic Places in 2007.