The calcium carbonate pools of Pamukkale have been depositing mineral-laden water for seventeen thousand years, building white travertine terraces that climb two hundred metres above the Çürüksu plain. The name translates directly to cotton castle, a reference to the bleached appearance of the formations when viewed from the valley floor. By the second century BCE, the Attalid dynasty of Pergamon had founded Hierapolis at the plateau's edge, drawn by the thermal springs that fed both the terraces below and a chain of bathhouses within the city itself. Today the site operates as a unified archaeological park, with Hierapolis recognised as one of the best-preserved Greco-Roman spa cities in Anatolia. The necropolis contains more than twelve hundred tombs, arranged along the road that once connected the city to Laodicea and Colossae. The theatre, carved into the hillside in the second century CE under Hadrian and Septimius Severus, seats fifteen thousand and retains much of its original stage building, including relief panels depicting the life of Dionysus and Apollo. The travertine pools themselves remain active, fed by springs that emerge at a constant thirty-five degrees Celsius and carry a mineral load so high that the overflow calcifies within hours of exposure to air. A Pamukkale day trip from Marmaris typically departs before dawn, covering the three-hundred-kilometre route inland through the Gökova basin and the Menderes valley. The journey crosses three climate zones, moving from the humid Aegean littoral into the drier continental interior of Denizli province. Most full-day itineraries allocate three to four hours within the archaeological zone, allowing time to walk the terraces barefoot — a conservation measure introduced in the nineteen nineties to reduce erosion — and explore the upper plateau where Hierapolis spreads across eighty-two hectares. The Hierapolis Archaeology Museum, housed in the restored Roman baths, displays artefacts from the site's excavation, including sarcophagi reliefs, cult statuary, and inscriptions that document the city's role as a religious centre dedicated to Cybele and later to Apollo. Some excursions include a stop at the Antique Pool, where submerged marble columns from a collapsed temple colonnade rest beneath thermal water. The site opens daily at half past six, with the earliest arrival window offering cooler temperatures and thinner crowds before the midday heat settles over the plateau. Entrance is thirty euros for foreign adults, covering both the travertines and the Hierapolis ruins. The conservation fee supports ongoing restoration work and monitoring of the spring flow, which has fluctuated in recent decades due to upstream water extraction.