The rock formations of Pamukkale are a series of natural shelves and ridges, terraces that have been turned white from the solidified chalky calcium deposits left behind as the thermal waters tumble into further basins clinging to the cliff edge below.
The ancient city of Hierapolis was built on top of the white "spa". The great baths were constructed with huge stone blocks and consisted of various closed or open sections linked together. There are deep niches in the inner section of the bath, library, gymnasium and other closed or open locations. The complex is now an archaeological museum.