One Park, Three Sites, Countless Stories

In one of the most transformative events of the 20th century, the Manhattan Project ushered in the nuclear age with the development of the world’s first atomic bombs. The effort to build atomic weapons began in 1942 with three secret communities across the nation. As World War II waned in 1945, the United States dropped the atomic bombs on Hiroshima and Nagasaki, Japan, forever changing the world.

A child wearing a green polo shirt interacts with an exhibit.

Top Ten Tips

Tips to make the most out of your visit to Manhattan Project NHP.

Mobile phone with mockup of app

New Mobile App

Experience and explore places with unique ties to the Manhattan Project. Download the app to learn more.

Several workers walking away from large industrial complex

Stakeholder Engagement

Learn more about Manhattan Project NHP's Stakeholder Engagement Project.

A large industrial building on an arid plain.

Hanford, WA

A secret factory that made plutonium.

A white-sided building with a green door sits on paved ground.

Los Alamos, NM

A covert lab that built the bombs.

Color photo of a large reactor face with mannequins in white suits.

Oak Ridge, TN

A hidden complex that enriched uranium.

Last updated: October 22, 2021

Contact the Park

Mailing Address:

Manhattan Project National Historical Park
c/o NPS Intermountain Regional Office
P.O. Box 25287

Denver , CO 80225-0287


505 661-6277
This phone number is for the Los Alamos Unit Visitor Center. You may also contact the Oak Ridge Unit Visitor Center at (865) 482-1942, or the Hanford Unit Visitor Center at (509) 376-1647.

Contact Us


Stay Connected