Miao Room is the largest known cave chamber by volume in the world. It is a part of the Gebihe cave system, which is located in Ziyun Getu He National Park, in Ziyun county of the Chinese province of Guizhou. The chamber, discovered by a French expedition called Gebihe'89 in 1989, measures in length, in width, has an area of and a volume of . In 2013 members of a British led expedition measured the chamber using 3-D laser scanners.