Chernobyl is a city in the Ukraine located about 56 miles (90 kilometers) northeast of the capital, Kiev.
Prior to the disaster and a subsequent evacuation, it was home to around 14,000 people.
At that time, it was still part of the Soviet Union.
The city was the location of the first ever nuclear power station to be built in Ukraine, but on the 26th of April, 1986, disaster struck when Reactor No. 4 exploded.
The town is still home to around 690 people, although it's now somewhat of a ghost town, with animals occupying many abandoned buildings.
Most of the residents live about 19 miles (30km) from the disaster site in the Chernobyl Exclusion Zone, and surprisingly, international tourists flock to the area.
But what exactly happened in Chernobyl?
That's what we'll find out today, in this episode of the Infographics Show, What Caused the Catastrophic Nuclear Accident in Chernobyl?
As CNN reported in 2016, if you visit Chernobyl now as a tourist, you'll be taken on a strict guided tour of what was once a busy, if not small, city.
Photographs show a place that has been frozen and overgrown, a kind of spooky remnant of a town where people once lived and worked, and where kids played on the now unused ferris wheel.