13. United States Holocaust Memorial Museum, Washington, D.C.

1.5 million

The Holocaust explains that its mission is to "advance and disseminate knowledge about this unprecedented tragedy; to preserve the memory of those who suffered; and to encourage its visitors to reflect upon the moral and spiritual questions raised by the events of the Holocaust as well as their own responsibilities as citizens of a democracy." The building, completed in 1993, was designed by Pei Cobb Freed and Partners, who explain that the space is "organized internally around the skylit Hall of Witness, a three-story arrival, distribution and circulation center that infuses stairs, walls, layered space and shadows with suggestive disquiet."