Semipalatinsk Test Site

The Semipalatinsk Test Site occupies a huge area of steppe on the southern bank of the Irtysh valley and was selected in 1947 for Soviet nuclear testing across a roughly 18,000 km2 polygon. The scientific and administrative complex was built in the northeast of the site; many of the test locations lie further west and south within the polygon. The site lies in what is today Abai Region of eastern Kazakhstan, relatively remote from major cities.

From 1949 until the late 1980s the Soviet Union carried out hundreds of nuclear explosions here, including the first Soviet atomic and the first Soviet air-tested thermonuclear blasts; testing moved over time from atmospheric tower shots to underground tunnel and borehole detonations at places such as Balapan and the Degelen mountain complex. Public pressure and political change led to the closure of the Polygon on 29 August 1991. The long history of testing left radioactive contamination and a complex legacy for local communities and the environment.

Since the 1990s international and Kazakh programs have worked to secure fissile material and to remediate parts of the area; a long secret operation to seal and stabilise plutonium-bearing waste in mountain tunnels was completed in the 2010s. Large parts of the polygon have been opened for limited tourism and research since about 2014, and the lack of farming in some zones has allowed wildlife to recolonize sections of the steppe. Visits are best organized from nearby towns and usually involve guided drives on unpaved tracks with restricted access to sensitive areas.

• Kurchatov (lab and administrative complex): The laboratory and town built to service the Polygon - often referred to in historical sources as Kurchatov or by local station names - contains Soviet-era research buildings and displays of the site’s administrative past.
• Degelen mountain tunnels: Degelen is a maze of sealed tunnel entrances and boreholes used for underground tests, including visible capped portals and reinforced drifts.
• Balapan and the experimental field: Balapan and the flat experimental fields west of the lab were used for atmospheric tower shots and show impact zones, monitoring posts and fenced-off test plots.
• Chagan crater lake: Chagan Lake, formed by an early test-created crater, is an unusual circular lake on the Polygon and an often-visited visual reminder of atmospheric testing.
• Memorials, abandoned villages and wildlife: Scattered memorials and empty settlements record local histories of exposure, while quieter tracts of steppe have become refuges for birds and mammals.

The nearest city and travel hub is Semey (formerly Semipalatinsk), which has road, rail and an airport; the administrative complex of the test site lies roughly west of Semey by several hours’ drive. Semey is the normal base for visits to the Polygon.

The last stretch across the steppe is on unpaved tracks and may cross restricted or remediated zones, so most visitors go with a licensed guide or a local driver from Semey; taxis or rental vehicles can cover the distance but check access and safety conditions locally before you go.

• Arrange visits through an experienced local guide or tour operator in Semey because parts of the Polygon remain restricted and conditions change.
• Do not enter fenced or signposted areas and follow all instructions about where to walk and park; some sites were remediated and others remain off-limits.
• Roads are rough and distances are long - carry water, sun protection and basic supplies for a full day on the steppe.
• Respect memorials and the local communities affected by testing when photographing or asking questions.