One of Turkey's most famous natural wonders, the pure white travertine terraces of Pamukkale ("Cotton Castle" in English) cascade down the slope looking like an out-of-place snowfield amid the green landscape.

Although the travertines are themselves a highlight of a Turkey trip, the vast and rambling ruins of Greco-Roman Hierapolis, an ancient spa town, lie scattered across the summit of this calcite hill.

After exploring the ancient theater, with its views across the countryside, and the remnants of the city's agora, gymnasium, necropolis, and grand gates, you can swim in the mineral-rich waters which made this ancient spa town famous, in the antique pool.

Afterward, walk down the travertine hill, wading through the pools of water in the upper terraces, to the small modern village of Pamukkale below.

For the best photographs, come at dusk when the travertines glow as the sun sinks below the horizon.