
Los Alamos National Laboratory, in collaboration with the National Nuclear Security Administration’s Los Alamos Field Office and the National Park Service, is opening the lottery for its first 2026 series of public “behind-the-fence” tours of Manhattan Project National Historical Park. Tours will take place twice each day on May 5, 6 and 7.
How the lottery works:
- Lottery registration period is open Feb. 23-March 4
- Register for the lottery
- Participants will be drawn at random from the pool of registrants and notified by March 31
- All registrants will be notified of the results via email
- Participants who registered for the lottery in the past but were not selected must register again for the May 2026 round of tours

These unique, half-day tours take participants to sites where Manhattan Project scientists made world-changing discoveries. Visitors will:
- Visit the original Pond Cabin, where physicist Emilio Segre’s team made the pivotal discovery that the “Thin Man” plutonium bomb design would not work.
- See Battleship Bunker, where experiments helped reveal crucial Manhattan Project discoveries.
- Walk through the Slotin Building, where a criticality accident occurred while Slotin was conducting an experiment.
- Hear from experts about what life was like in Los Alamos when it was a secret city during World War II.
Participants must be at least 18 years old, U.S. citizens, and able to provide proof of citizenship at tour check-in. As an active national security laboratory, Los Alamos National Laboratory has strict entry requirements for visitors; read registration materials carefully for details. These tours are not open to Lab employees.
Lottery registration is online only. All future tour opportunities, as well as ongoing park updates, will be posted online.
Read more about ways to visit Los Alamos, New Mexico and see Manhattan Project history where it happened.
Contact
Public Affairs | media_relations@lanl.gov





