Peter Walker Ukraine announces official tours of the 1986 nuclear disaster site. LESSONS FROM AN ACCIDENT: Visitors can now learn more about the tragedy. A 2007 file photograph of the abandoned town of Pripyat and the now closed Chernobyl nuclear power plant in the background. Already been to North Korea? Hiking in Afghanistan too last year? Fear not. Tourism has a new frontier: the site of the world's biggest civilian nuclear disaster. From next year the heavily contaminated area around the Chernobyl power plant will be officially open to tourists with an interest in post-apocalyptic vistas, late-period Soviet history, or both. Ukraine's emergency situations ministry said on December 13 that visitors would be offered tours inside the 50km exclusion zone set up after reactor four at the plant exploded on April 26, 1986, showering northern Europe in radioactive fallout. The disaster killed an unknown number of people