20 May 2008
Hot springs in Turkey characterized by a high content of hydrogen carbonate and calcium, leading to the precipitation of calcium carbonate (chalk) in the form of terraces, frozen waterfalls, and stalactites.
"These sources were well-known in antiquity. They were described by the Roman architect Vitruvius. The Phrygian Greeks built Hierapolis on top of the hill. They ascribed medical properties to the spring water, bestowed by the gods, especially Asklepios (demigod of medicine) and his daughter Hygieia (goddess of health, cleanliness and sanitation), under the protection of Apollo (god of medicine and healing)." (text from Wiki, photo from Pixdaus)(more impressive if you click to view full-size)