Visit Pamukkale

Colossal stone heads ringing a mountaintop royal tomb from the 1st century BC.

Sunken Byzantine reservoir under Istanbul, its columns rising from black water.

Xi'an's buried army of clay warriors.

The Parthenon and its temples on the rock above Athens — the birthplace of democracy, best climbed at opening time.

Mineral springs that have petrified into white waterfalls of stone above the Oaxaca valleys, with cliff-edge pools you can swim in.

Maya ruins on a cliff above a turquoise Caribbean beach — the only ancient city built right on the sea.

Stand among the cloud-wrapped ruins of Machu Picchu, the 15th-century Inca citadel perched high above Peru's Sacred Valley

Walk the streets of a Roman city frozen mid-life by Vesuvius in 79 AD — ruts, frescoes, bakeries and all