Scenic Doulong Valley in Northwest China’s Shaanxi Province is home to an unusual natural phenomenon - thin symmetrical ice crystals that resemble pairs of butterfly wings. Cheng Xiwu, a local resident, was one of the first to notice them. The 63-year-old has since been leading his family members to clear and maintain paths through the area to help more people visit what he is calling “Butterfly Valley”. Photos: VCG