IN THE CHORNOBYL EXCLUSION ZONE, Ukraine – What was supposed to be a routine test at the fourth reactor of the Chornobyl Nuclear Power Plant turned into the world’s deadliest nuclear accident in history on April 26, 1986.

An aerial view of the government-run 1,000-square-mile Chornobyl Exclusion Zone along with the Prypiat River that dissects the area and which is a tributary to the Dnipro River.