Where did nuclear explosions take place?
The Semipalatinsk test site sits in the northeast of Kazakhstan, south of Pavlodar. It opened in the late 1940s as part of the Soviet nuclear weapons program. On August 29, 1949, the USSR conducted its first atomic bomb test here.
Between 1949 and 1989, the site hosted 125 ground and air explosions, including the first Soviet hydrogen bombs. When open air testing ended in 1963, underground testing continued, often conducted in mines and underground galleries within the same area. Cumulative tests near Semipalatinsk, counting underground events, exceed 450. This record reflects a long era of weapon development and verification in a remote steppe environment.
The storage complex covers more than 18 square kilometers, with a diameter around 100 kilometers. Much of the area remained clearly defined and protected, yet some zones still show elevated radiation levels. Official use of the site ended in 1991, but there are places where the background radiation is still above normal. The broader area was not always clearly marked or secured, and locals have lived nearby for years, with livestock grazing and occasional visits by travelers and curious explorers.
“Atomic” lakes
Even after many decades, the landscape of Semipalatinsk resembles an expansive steppe. Without a guide, visitors might not notice anything remarkable, yet shells and craters from explosions dot the terrain in places, some standing a few meters high.
One notable feature is a 30-meter tower that once supported RDS-1, the USSR’s first atomic bomb. The tower was toppled by a blast, leaving behind a reed-filled lake about five meters in diameter that now resembles a natural pond. Other lakes at the site are larger and sport steep, almost artificial shores that hint at their man-made origins. The so-called 100-meter TNT lake is not a direct weapon test lake but was created during a 1963 experiment that used 20,000 tons of explosives sourced from across the Union a six-month effort to stage the blast.
Lake Chagan, also known as Atomic Lake, formed on January 15, 1965 after a 170-kiloton underground detonation at a depth of 170 meters. The resulting reservoir measures roughly 430 meters across and 100 meters deep. The water remained highly contaminated for years, but today it is monitored, and fishing occurs under controlled conditions despite ongoing caution regarding safety and regulations.
Ruins and museum
Explosions did not occur in open space alone. Command centers, measurement stations, and observation points were built to study effects and to guide tests. Settlements with practical houses were constructed, while trenches were dug and bunkers placed, offering living models to assess damage and outcomes. Relative to the overall cost of the nuclear program, constructing these facilities was a small fraction of the budget, yet many of the target buildings have not survived intact.
Today, visitors can still spot many auxiliary structures in the landscape, including watchtowers known for their distinctive buttresses that resisted blast waves. By 2017, most equipment had been removed or looted, leaving behind a tapestry of ruins. Some underground facilities remain recognizable, including a small subway-like passage that survived a pair of low-power detonations nearby.
In nearby Kurchatov, a dedicated museum preserves items collected from bunkers and control rooms. Exhibits include control panels, oscilloscopes, spectrometers, gamma detectors, seismic sensors, cameras, and a wide array of historical photographs documenting tests and their effects on infrastructure, equipment, and experimental animals.
Increased radiation background
While the main test zones are considered controlled, certain areas around Semipalatinsk exhibit higher radiation levels. The risk lies more in dust and contaminated soil clinging to clothing than immediate radiation during a short visit. Protective clothing and overshoes are advised for anyone visiting the epicenter area within the Experimental Zone.
Visitors may encounter chunks of clumped earth that resemble volcanic glass or dried fuel oil. These so-called kharitonchiki carry low radioactivity and are safe if stored properly. The distribution of higher radioactivity is uneven, so unaccompanied travel is not recommended. Several parts of the site are off limits and will remain uninhabitable for thousands of years.
How to take
Today the city of Kurchatov, once sealed off, is open to visitors. Escorts are required for tours to the test areas, and independent trips are not permitted. One popular option is a prepared tour offered by adventure-focused travel agencies. A three-day itinerary starting from Astana includes the museum, testing grounds, and a visit to the abandoned military town of Chagan. The closure of the test site on August 29, 1991, marks the end of a long era of testing activities and research in this region.
Note: information about the site reflects historical operations and preservation efforts. As with sensitive locations, travelers should respect safety guidelines and local regulations while exploring the landscape and the remnants of this period in history. — attribution: regional historical archives and field reports