Pamukkale, meaning "cotton castle" in Turkish, is a natural site in southwestern Turkey. The area is famous for a carbonate mineral left by the flowing water.

The Turkish name refers to the surface of the shimmering, snow-white limestone, shaped over millennia by calcium-rich springs. Dripping slowly down the vast mountainside, mineral-rich waters foam and collect in terraces, spilling over cascades of stalactites into milky pools below.

Pamukkale is a tourist attraction. It is recognized as a World Heritage Site together with Hierapolis. Hierapolis-Pamukkale was made a World Heritage Site in 1988.

Known as Pamukkale (Cotton Castle) or ancient Hierapolis (Holy City), this area has been drawing the weary to its thermal springs since the time of Classical antiquity.

Tourism is and has been a major industry in the area for thousands of years, due to the attraction of the thermal pools. As recently as the mid-20th century, hotels were built over the ruins of Hierapolis, causing considerable damage.

The hotels built in the 1960s were demolished as they were draining the thermal waters into their swimming pools and caused damage to the terraces. The water supply to the hotels is restricted in an effort to preserve the overall site and to allow deposits to regenerate.

Aside from a small footpath running up the mountain face, the terraces are all currently off-limits, having suffered erosion and water pollution at the feet of tourists.

More Info: en.wikipedia.org