RICHLAND, Wash. - In a cramped control room, a bright yellow sticker cautions workers about critical radiation alarms. The sign is a novelty now, stuck on a wall between dials that haven't spun in decades, but it hints at the enormousness of the plant's onetime mission.

The world's first full-scale nuclear reactor is just one stop on a tour of the Hanford Nuclear Reservation. The federal government created the site in the 1940s as part of the top-secret Manhattan Project to build the atomic bomb.

Today, more than two decades after it stopped producing plutonium, Hanford is the nation's most contaminated nuclear site. A cleanup is expected to continue for years.

Still, the sprawling land of dust and sagebrush - about half the size of Rhode Island - will draw 2,000 tourists this year.

Some seek out the history of America's nuclear age. Others come to reminisce about the days they or their loved ones spent working in the desert city that sprang up overnight. Then there are those who are concerned about the government's environmental stewardship.

Tourists aren't allowed close enough to the cleanup operations to be in danger from contaminants, largely found in the soil and water.

From a distance, visitors watch workers in white protective suits bury mercury-contaminated soil in a landfill. They gawk at massive cranes brought in to build a plant that will encase radioactive waste in glass.

"We love it. We love to have people come. The American people own the site, and they ought to be able to see it," said Michele Gerber, spokeswoman for cleanup contractor Fluor Hanford Inc. and a Hanford historian.

Tourism in the nuclear industry isn't new.

In 1949, the American Museum of Atomic Energy opened its doors in Oak Ridge, Tenn., guiding visitors through the peaceful uses of atomic energy. It has since been renamed the American Museum of Science and Energy.

The Atomic Testing Museum in Las Vegas traces a half-century of nuclear weapons testing, including the world's first explosion of a nuclear device, the Trinity test on July 16, 1945.

In Albuquerque, N.M., the National Atomic Museum offers exhibits and programs about the people and events that shaped the nuclear age.

The U.S. Department of Energy, which manages Hanford, posts tour dates for the site on its Web site each spring. Visitors must be U.S. citizens and register online.

"It's the first time we've ever been able to get onto it. It's pretty difficult, but I think it's wonderful. I've always wanted to come back," said Betty Breitenfeldt, 85, of Prosser, Wash.

Breitenfeldt was hired in Iowa to come to Hanford as an office worker in June 1944, shortly after the government picked the rural land to house some of the Manhattan Project. The jobs were taken by the time she arrived. She ended up waiting tables in one of eight mess halls built to feed the 50,000 people lured to southern Washington by jobs. Few knew they were there to build the nuclear reactor. Some joked the plant would produce toilet paper.

Only after the United States dropped the bomb on Hiroshima on Aug. 6, 1945, did the realization hit home: The B Reactor had produced the plutonium for the Trinity test a month earlier. Then it made the plutonium for the bomb dropped on Nagasaki three days after Hiroshima.

Acres of contaminated debris - such as clothing, equipment and pipes - are buried underground. Miles of contaminated groundwater lie next to the Pacific Northwest's largest waterway, the Columbia River.

The B Reactor is the showpiece of the tours, which also highlight the remnants of World War II and Cold War weapons production.

"It's interesting to see, or to think about, where our country was in the '40s and what we had to do, versus what we've learned since about nuclear material and about the environment and to see what they're doing with it," Danielle McGurk, 39, of Seattle, said as she toured the site.

Gerber conceded one goal of the tours is to give people an understanding of how complicated the cleanup is. The other is to ensure they appreciate Hanford's history. "Hanford was the battleground of the Cold War, and that story has never really been told, because the Cold War has only been over for 17 years," she said. "We are on the forefront of telling that story, and it's very exciting."

For information on tours of the Hanford nuclear site, go to