On the 26th of April in 1986, an explosion in Ukraine sparked the world's worst nuclear accident.
As well as having a devastating impact on parts of Eastern Euope, it was also to have a long-lasting effect on this region.
The accident sent a cloud of radioactivity across western Europe, spreading above Cumbria - where the heavy rain washed it down onto the fells, causing problems to farmers for more than 20 years.
Wet land in the Lake District stored contamination and any sheep grazing on it showed high levels of radiation.
Before they could be sold, sheep had to be monitored for a week to stop infected meat from entering the food chain. The last restrictions were lifted in 2012.
As the radioactivity reached Sellafield nuclear plant, it triggered the sites alarms. It caused wild chaos and confusion as staff tried to figure out if the high levels of radioactivity were from a major incident on the west Cumbrian plant itself.
Thirty years on, the accident has changed the way nuclear organisations work together around the world to try and prevent anything like Chernobyl happening again.