Huanglong Scenic Area (Yellow Dragon Valley), which is known for its colorful travertine pools formed by calcite deposits, as well as diverse forest ecosystems, snow-capped peaks, waterfalls and hot springs. As a world-famous travertine landscape, Huanglong is shaped by repeated glaciation, the unique terrain structure, the tufa formation, the stratum of carbonic acid rock and climate conditions such as Arctic-alpine sunlight Arctic. In 1992, it was officially listed as a World Natural Heritage Site by UNESCO.