23/04/2022
Turkey's mysterious 'portal to the underworld'
The ancient city of Hierapolis has long hidden a poisonous secret in its mysterious "Gate to Hell". But modern science has finally uncovered the truth behind the Roman myths.
In Pamukkale in western Turkey, an enormous white rock formation towers over the surrounding plain. The gleaming mountain of petrified limestone cascades to the valley floor, creased with frozen stalactites and tessellated with hundreds of pools of sparkling turquoise water.
These otherworldly formations are travertines, limestone cliffs slowly created over 400,000 years by the bubbling up of mineral springs. As the water flows down the hillside it degasses, leaving behind a vast deposit of bright white calcium carbonate that's almost 3km long and 160m high. This is not the only place where travertines occur – Huanglong in China and Mammoth Hot Springs in Yellowstone National Park are other famous examples – but the ones at Pamukkale are the largest and arguably the most magnificent in the world. They're one of the country's most popular visitor attractions, and are so spectacular that the Unesco World Heritage Site's name means "cotton castle" in Turkish.
Until the pandemic hit, more than 2.5 million people a year made the journey here from Izmir or Istanbul, spilling out of tour buses at the top of the dazzling plateau and swarming across the landscape like ants on a gigantic mound of sugar before piling back on board and heading on to the beaches of Bodrum or the historic ruins of Ephesus.
But visitors who simply dip their toes in the vivid mineral pools and take a selfie in front of the dripping natural columns before moving on are missing a trick. Because perched at the very top of Pamukkale's white crags sits an even more fascinating attraction: the ruins of the beautiful ancient city of Hierapolis.
Hierapolis was founded by the Attalid kings of Pergamon at the end of the 2nd Century BC before being taken over by the Romans in 133 AD. Under Roman rule, it became a thriving spa town; by the 3rd Century, visitors were coming from all over the Empire to admire the landscape and bathe in the supposedly healing waters. The success of the city is still visible in its impressive arched entrance gate, its colonnaded main street and its beautifully restored amphitheatre, all built from the same local travertine that glows golden in the hot Turkish sun.
