In September 1945, Dr. J. Robert Oppenheimer, scientific director of the Manhattan Project, and General Leslie R. Groves, commanding general of the Manhattan Project, returned to ground zero at the Trinity Site, on what is now the White Sands Missile Range in New Mexico. A small portion of twisted metal was all that remained of the Trinity tower, from which the world’s first nuclear device was detonated on July 16, 1945.

Established November 10, 2015, the Manhattan Project National Historical Park (MAPR) is managed through a collaborative partnership by the U.S. National Park Service (NPS) and the U.S. Department of Energy (DOE) to preserve, interpret, and facilitate access to key historical resources associated with the Manhattan Project.

The Manhattan Project was a massive, national mobilization charged with producing a deployable atomic weapon during World War II. The project culminated with the United States dropping two atomic weapons on Hiroshima and Nagasaki, Japan. Coordinated by the U.S. Army Manhattan Engineer District, Manhattan Project activities were dispersed to numerous locations across the United States. MAPR incorporates three of the most significant Manhattan Project sites: Oak Ridge, Tennessee; Los Alamos, New Mexico; and Hanford, Washington. For more on the Manhattan Project, including multimedia, please visit /manhattanproject.

DOE performs management, operations, maintenance, and preservation activities for the historic Manhattan Project sites currently under its jurisdiction. NPS provides administration, interpretation, and education at the three park sites, and supplies technical assistance in support of resource preservation. The two agencies collaborate in identifying and developing partnership arrangements and other strategies to tell the complete story of the Manhattan Project and its legacy. In November 2016, DOE made its Office of Legacy Management (LM) responsible for coordinating among the DOE program offices that are implementing the MAPR mission.