A memorial for the Chernobyl Nuclear Disaster victims is pictured in front of the Sarcophagus covering the destroyed 4th block of Chernobylâs power plant on March 28, 2011. Chernobyl nuclear power plant, where the world’s worst nuclear disaster took place in April 1986, and the 30-km zone around it remain unhabited until now. Ukraine and its neighbors mark on April 26 the 25th anniversary of the catastrophe. AFP PHOTO/GENYA SAVILOV