Pamukkale (Turkish for 'cotton castle') is a natural, mineral-rich thermal site in Denizli Province in southwestern Turkey that looks like a winter wonderland but has actually warm water running down the hillside, leaving white calcium deposits called travertines that coat the hill like a frozen white curtain. This area has been drawing visitors to its thermal springs since the time of Classical antiquity, the period of cultural history between the 8th century BC and the 6th century AD centered on the Mediterranean Sea. It was added as a UNESCO World Heritage Site in 1988.

Pamukkale is considered a natural health spa thanks to the many benefits it provides for its visitors. According to many, the water provides a cure against asthma and rheumatism.
Additionally, the water brings benefits to the skin, eyes, helps recover from high blood pressure, kidney stones, stroke, physical exhaustion, circulatory issues, digestive maladies, chronic disorders, and nutritional disorders.

Unfortunately due to bad management and no government protection, in the early to mid-20th-century hotels were built over the ruins of Hierapolis, causing considerable damage. A road was built from the valley over the terraces, and motorbikes were allowed to go up and down the slopes. When the area was declared a UNESCO World Heritage Site in 1988, the hotels were demolished and the road removed. The damaged pools were replaced with artificial pools.

Today to protect the thermal pools the access to the natural terraces is not allowed, except the artificial ones, and visitors are asked to follow the pathway.