chernobyl
Chernobyl was a nuclear power plant located near Prypyat, Ukraine that underwent a meltdown and explosion on April 26, 1986. The disaster was the worst atomic accident in history. The area is still quarantined to this day.
This tag refers to both the nuclear power plant, as well as the semi-abandoned Ukrainian town on the edge of the Exclusion Zone (and apparently to mis-identified images set in Prypyat)