The Chernobyl disaster occurred on April 26, 1986 at the Chernobyl Nuclear Power Plant. This and the 2011 Fukushima Daiichi incident in Japan are the only two level 7 (major accident) events on the International Nuclear Event Scale to have occurred. Level 7 is the most severe level of civilian nuclear accident.
Chernobyl was a power plant located in Pripyat, a village in what was then the Ukrainian Soviet Socialist Republic of the Soviet Union. The Soviet Union having collapsed in the interim, Ukraine is now a sovereign state. Pripyat is located in northern Ukraine near the border of Belarus.
After the nuclear accident, the contaminated region surrounding the power plant was evacuated, creating the Chernobyl Exclusion Zone, an area that is now a ghost town, visited only by a few intrepid tourists and scientists studying the long-term effects of radiation on the ecosystem. Much of it is now a wildlife reserve.
In the absence of human habitation, the ecosystem has proven surprisingly robust, with small animal populations recovering within a decade of the disaster. Although scientific studies are still in progress and long-term effects on animal genetics may only show up in future generations, wildlife now appears to be thriving in the area. The fear of radiation that keeps people (even poachers) from returning to the area—as well as the laws protecting it from trespassing—have proven a net positive for wolf and other predator populations.