What are the Pamukkale terraces?
Quick answer
Pamukkale is a hillside of bright white travertine terraces and warm, turquoise pools in Denizli Province, southwestern Turkey. Its name means “cotton castle” in Turkish. Hot springs rich in calcium carbonate flow down the slope and leave mineral deposits that build up into terraces.
Key facts
- Location
- Denizli Province, Turkey
- Meaning
- Cotton castle
- Water temperature
- About 35 °C (95 °F) at the source
- UNESCO
- Hierapolis-Pamukkale, listed 1988
How the terraces formed
The terraces are still growing today, built by the same slow chemistry that has worked here for thousands of years.
- Rainwater seeps underground and is heated by geothermal activity.
- It dissolves limestone and carries calcium carbonate to the surface.
- As the warm water flows down the slope, it releases carbon dioxide.
- Calcium carbonate settles out as a soft gel that hardens into white travertine.
- Over thousands of years, this built up terraces about 2,700 m long and 160 m high.
It’s the same chemistry that makes soda fizz and limescale form in kettles.
Hierapolis: a Roman spa city
On top of the terraces lie the ruins of Hierapolis, founded in the 2nd century BC. People came from across the Roman world to bathe in its healing waters.
| Site | Highlights |
|---|---|
| Theater | A well-preserved Roman theater for about 12,000 people |
| Necropolis | One of the largest ancient cemeteries in Turkey |
| Antique Pool | A pool, often called “Cleopatra’s Pool,” where you can swim among fallen marble columns |
| Plutonium | A “gate to the underworld” filled with deadly carbon dioxide gas |
Saving the terraces
In the late 20th century, hotels built on the terraces used the spring water, and the white surfaces began to turn gray. Hotels were removed, water flow is now carefully managed, and visitors may only walk barefoot on designated paths to protect the travertine.
Similar places
Travertine terraces also occur at Mammoth Hot Springs in Yellowstone (see the Grand Prismatic Spring), Huanglong in China and Badab-e Surt in Iran.
For another of Turkey’s ancient wonders, see what Göbekli Tepe is.
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