The brilliant-white, terraced pools of the Pamukkale “cotton palace” hot springs have lured people to this area for well over two millennia and are the reason the Greco-Roman town of Hierapolis exists. Built just above the half-mile-wide, 65-foot-tall travertine wonder in 190 B.C., this ancient “spa town” has ruins of temples, a well-preserved theater, and a Sacred Pool where visitors float above broken Roman columns.