The Cotton Castle has nothing to do with any kingdom. It is a breathtaking natural wonder, which looks like frozen waterfalls but in reality is a white cliff covered with white minerals, left by the flowing down, hot water from an underground spring. This process has been running unstoppably for over 14000 years. Around the 2nd century BC, the ancient city of Hierapolis developed right above the cliff, making Pamukkale an ancient spa.
Ever since people discovered Pamukkale, they bathe in the natural pools, especially in the summertime. Nature didn't seem to be bothered by this fact and the terraces remained in almost untouched condition until the last century, when some modern hotels were built nearby and negatively affected the spring's natural processes.
I didn't notice when it got very late, I had to skip the ancient ruins and hurry not to miss my bus.