The Mosler bank vault, built to determine the effects of nuclear weapons on civil structures, survived a 37-kiloton blast in 1957 at the Nevada National Security Site. After the explosion workers removed the vault’s door and discovered that the simulated currency inside was undamaged. (Jim Lo Scalzo)

The remains of Hanford High School, which will become part of the upcoming Manhattan Project National Historical Park, are seen at the Hanford Site in Hanford, Wash. The site was used to make plutonium for nuclear weapons and is now one of the most toxic nuclear sites in the Western Hemisphere. (Jim Lo Scalzo/EPA)

Sprinkled throughout the back roads of America are the remains of Armageddon. Or what could have been Armageddon had the Cold War between the United States and the Soviet Union suddenly gone hot.

In the coming months, the National Park Service and the U.S. Department of Energy will establish the Manhattan Project National Historical Park — preserving once-secret sites in Los Alamos, N.M., Oak Ridge, Tenn., and Hanford, Wash., where scientists raced to develop the world’s first atomic bomb. Public tours at these sites are already intensely popular, selling out within days. The Park Service is trying to improve access to these sites to meet the increasing public interest. Veteran photojournalist Jim Lo Scalzo of European Press Agency has been documenting many of these site–hidden in plain site–for the past year in a project titled “Next Exit: Armageddon”.

Yet elsewhere in the United States, the ruins of the Manhattan Project, and the arms race that followed, remain overlooked. In North Dakota, pyramid-like anti-missile radar, built to detect an incoming nuclear attack from the Soviet Union, pokes through the prairie grass behind an open fence. In Arizona, a satellite calibration target used during the Cold War to help U.S. satellites focus their lenses before spying on the Soviet Union sits covered in weeds near a Motel 6 parking lot. In South Dakota, decommissioned nuclear missiles still aim skyward; in Nevada and New Mexico, the remains of nuclear testing still scar the desert. And in a suburban Chicago park, where visitors jog and bird watch, nuclear waste from the world’s first reactor — developed by Italian physicist Enrico Fermi for the Manhattan Project in 1942 — sits buried beneath a sign that reads “Caution—Do Not Dig.”

— From “Next Exit: Armageddon” by Jim Lo Scalzo/EPA

Two rocket fuel handler outfits, which were worn by propellant transfer system technicians, are displayed at the Titan Missile Museum, which preserves a Titan II intercontinental ballistic missile, in Sahuarita, Ariz., in April. (Jim Lo Scalzo)

The control room of the X-10 graphite reactor, the world’s second reactor after Enrico Fermi’s so-called Chicago Pile, is seen at Oak Ridge National Laboratory in Oak Ridge, Tenn. Built in secret during the Manhattan Project, the reactor supplied plutonium to nuclear scientists working at Los Alamos. (Jim Lo Scalzo/EPA)

The loading face of the X-10 graphite reactor is seen through the window of the control room at Oak Ridge National Laboratory. (Jim Lo Scalzo/EPA)

Tourists are seen in a long-exposure image visiting Trinity Test Site, where on July 16, 1945, scientists working with the Manhattan Project detonated the world’s first atomic bomb, on White Sands Missile Range just outside San Antonio, N.M. The Department of Defense allows the public to visit the site on just two days a year. (Jim Lo Scalzo/EPA)

A decommissioned Titan II intercontinental ballistic missile sits in an underground silo at the Titan Missile Museum in Sahuarita, Ariz., in April. (Jim Lo Scalzo/EPA)

The room that would have served as the House of Representatives in the event of a nuclear war is seen in a once-secret nuclear bunker built for members of Congress beneath the Greenbrier, a four-star resort near White Sulphur Springs, W.Va. The 112,544-square-foot bomb shelter included enough beds and supplies to accommodate all the lawmakers. (Jim Lo Scalzo/EPA)

Decontamination showers inside a once-secret nuclear bunker built for members of Congress are seen beneath the Greenbrier. (Jim Lo Scalzo/EPA)

The assistant launch control officer’s station is seen at the Delta 01-Launch Control Facility, the former control center of a Minuteman missile, just outside Wall, S.D., in March. (Jim Lo Scalzo/EPA)

A pressure monitor panel is among some of the vintage switches and indicators inside the main control room of Hanford’s historic B Reactor, the world’s first, full-scale nuclear reactor, on the Hanford Site in Washington state in May. (Jim Lo Scalzo/EPA)

The atomic cloud logo of the Richland High School Bombers, which reflects the pride in the Richland area for the community’s role in the development of the Manhattan Project and the end of WW II, decorates the floor of the high school’s gymnasium in Richland, Wash. (Jim Lo Scalzo/EPA)

Tourists walk through a blast door at the Delta 01-Launch Control Facility, the former control center of a Minuteman missile, just outside Wall, S.D. After the missile site was deactivated in 1994, the National Park Service turned the facility into the Minuteman Missile National Historic Site. (Jim Lo Scalzo/EPA)

The remains of a pyramid-like anti-missile radar, part of the the Stanley R. Mickelsen Safeguard Complex, which was completed in 1975 during the Cold War to detect an incoming nuclear attack from the Soviet Union, are seen just outside Nekoma, N.D. (Jim Lo Scalzo/EPA)

The world’s first, full-scale nuclear reactor, the historic B Reactor, is seen from the window of a bus tour on the Hanford Site in Washington state in May. (Jim Lo Scalzo)

Western wheatgrass has grown in and around the former launch site of a Minuteman intercontinental ballistic missile just outside Wall, S.D., in March. All that remains of the launch facility is a barbed-wire fence around an empty field. (Jim LoScalzo/EPA)