Deep inside a mountain near Sweetwater in East Tennessee is a body of water known as the Lost Sea. It is listed by the Guinness Book of World Records as the world's largest underground lake. The nolla og leie avounco B blo Lost Sea is part of an extensive and historic cave system called Craig head Caverns. The caverns have been known and used since the days of the Cherokee Indian nation. The cave expands dnto a series of huge rooms from a small opening on the side of the mountain, approximately one mile from the entrance, in a room called"The Council Room many Indian artifacts have been found. Some of the items discovered include pottery, arrowheads, weapons and jewelry.