Pamukkale (meaning "cotton castle" in Turkish) is a natural wonder. It's a hilly area covered with calcium deposits and has warm water flowing. From far it looks like a hill covered with snow or cotton. Somewhere deep in the earth beneath the area lies a vast source of water heated by volcanic lava. The water dissolves pure white calcium, becomes saturated with it, and carries it to the surface where it bursts forth and warm, mineral-rich water runs down the steep hillside. Cooling in the open air, the calcium precipitates from the water, adheres to the soil and forms white calcium travertines (terraces). Various sizes of pools of water are formed in travertines. Just above the travertines lies a Greek-Roman spa city, Hierapolis, which has considerable ruins and a museum. Pamukkale was recognized as a World Heritage Site in 1988 together with Hierapolis. link to my gallery of Hierapolis : https://pbase.com/cemilgursen/hierapolis_turkey