Manhattan Project National Historical Park

If science, secrecy, and history intrigue you, then a visit to the Manhattan Project National Historical Park (MPNHP) should be on your bucket list. The MPNHP preserves and interprets the nationally significant historic sites, stories, and legacies associated with the top-secret race to develop an atomic weapon during World War II.

MPNHP is the only national park managed in partnership by the Department of Energy and the National Park Service and includes locations in each of the three secret cities created for the Manhattan Project: Hanford, Washington; Los Alamos, New Mexico; and Oak Ridge, Tennessee. Together, these three sites share the complex story of one of the most profound historical events of the 20th century.

In the Tri-Cities, the Hanford site of the MPNHP includes the B Reactor National Historic Landmark, the first full scale plutonium production reactor in the world.

The Hanford site also includes the pre-war Hanford High School, Bruggemann’s Agricultural Warehouse, White Bluffs Bank, and Hanford Irrigation District Pump House, which together provide perspective on the sacrifices made for the Manhattan Project.


Free tours of the pre-war historic sites and the B Reactor are typically offered by the Department of Energy from April through early November. Reservations for the tours are required to guarantee seats; however, walk-in visitors may join a tour if space becomes available. The tours are four-hours long and the registration process is easy.

The Pre-War tours include stops at the historic pre-war structures and share stories of the communities along the Colombia and their displacement to make way for the Manhattan Project in 1943.


Eighteen months after the start of construction, Hanford produced the plutonium used in the Trinity Test on July 16, 1945. Tours of the B Reactor National Historic Landmark share the scientific achievement of building the world’s first full-scale plutonium production nuclear reactor. The B Reactor attracts more than 10,000 visitors per year from all 50 states and more than 50 countries. The MPNHP Hanford Site Visitor Center is located in Richland and serves as the meeting location for the park tours. There are also exhibits, videos, and a gallery of historic photos that change every six months. National Park enthusiasts can receive passport stamps at the visitor center and Junior Rangers can complete junior ranger books on both tours. Upon successful completion of the junior ranger book, new junior rangers earn a one of a kind MPNHP junior ranger badge or patch!

Every year, the park offers special events from a bike ride around and concerts in the B Reactor to youth-focused ranger programs in the Tri-Cities. Make plans to check out the Manhattan Project National Historical Park on your next trip to the Tri-Cities!

"Free tours of the pre-war historic sites and the B Reactor are typically offered by the Department of Energy from April through early November."