When the people of Tomioka were finally allowed short visits back to their homes after the 2011 Fukushima No. 1 nuclear power plant disaster, one of the first things they did was to prune the mountain town's languishing cherry trees.

After years of intermittent tending, the century-old trees, just 10 kilometers from the destroyed nuclear plant, returned to full glory. Kiyonori Watanabe, who has lived nearby his entire life, stops his car in front of a metal barricade and pulls up a photo on his phone: clouds of delicate, pink sakura blossoms.

This is as far as he can go. Nine years after the worst nuclear disaster since Chernobyl, the street lined by the trees is still uninhabitable. Other neighborhoods deemed safe now have only a fraction of their former population.