The Chernobyl disaster was the worst nuclear accident in history. During a late-night safety test on April 26, 1986, at the Chernobyl Nuclear Power Plant in present-day Ukraine, a combination of design flaws and operator errors triggered a massive power surge, leading to a pair of explosions that released radioactive material across large parts of the Northern Hemisphere.
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It now spans beyond the initial 30-kilometer radius around the nuclear plant to include surrounding areas found to have significant radioactive contamination. Aside from a handful of elderly self-settlers, permanent residency is banned, and access remains tightly controlled due to lingering radioactive contamination.
A subculture of thrill-seekers, driven by a desire for rebellion and adventure, is representative of dark tourism in the region. Some stalkers sneak past militia posts to venture into abandoned ruins, risking radiation exposure while scavenging for ruins of the past.
Within the area—roughly the size of Yosemite National Park—animals such as wolves, bears, and feral dogs descended from the pets left behind have gradually adapted to low-level radiation. Eastern tree frogs in the area have darker skin than usual, which may have helped protect them from ionizing radiation.
The group—collectively referred to as "liquidators"—included firefighters, military troops, miners, engineers and sanitation crews. Beyond clearing radioactive debris and performing decontamination work, they confined radioactive material to prevent its spread into groundwater.
The first structure—built to last 20 to 30 years—served as a covering for the exploded reactor and was built from about 16 million pounds of steel. In 2016, a new containment shell was constructed nearby and rolled onto the previous structure before being finalized in 2019.
Large doses of ionizing radiation can damage the body within minutes, particularly in the bone marrow and inner layer of the digestive tract. Victims may briefly seem fine before rapidly deteriorating as immune failure, infection and organ collapse set in.
This video shows how a 1986 safety test at Chernobyl spiraled out of control—leading to a massive rise in temperatures, an explosion and reactor meltdown that produced the largest civilian nuclear disaster in history.
A 2023 study identified that packs of dogs located just 16 kilometers (10 miles) apart within the exclusion zone were more genetically different from one another than from stray dogs hundreds of kilometers away. Rather than radiation, this is likely the result of inbreeding within isolated packs.
Completed in 2016, the "New Safe Confinement" is a €1.5B megastructure—the largest movable structure ever built. It was assembled next to the damaged reactor, then rolled into place along a special track to seal the site for at least 100 years.
Americans first heard about the Chernobyl nuclear disaster two days after the event, once abnormal radiation was detected in nearby countries. This forced Soviet officials to acknowledge the catastrophe publicly for the first time a few days after it occurred.
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