Before September 11, 2001, visitors were allowed walk-in tours of Y-12/Oak Ridge National Laboratory (865/574-7199, www.ornl.gov). But in today’s security-anxious world, casual visitors are not allowed on the campus of the nuclear plant without an advance reservation.

Call to arrange a tour, or get on one of the public bus tours offered in collaboration with the Museum of Science and Energy. These tours run daily during the months of June–September. To get on board the bus tour you must sign up in person at the Museum of Science and Energy before 9 a.m. on the day of the tour. The bus leaves at noon and returns at about 2:30 p.m. The bus tour is free with paid admission to the museum.

If you’re short on time, or don’t want to get tangled up at the AMSE, then head for the K-25 overlook (Hwy. 58), a mini-museum and viewing station located about 10 miles south of Oak Ridge. You’ll drive through the city’s industrial park before arriving to the overlook. Inside a small enclosed building is a short version of Oak Ridge’s history. Outside you can see the K-25 plant as well as other Oak Ridge infrastructure. It is not scenic, but it’s still a view.