Stand among the cloud-wrapped ruins of Machu Picchu, the 15th-century Inca citadel perched high above Peru's Sacred Valley
Xi'an's buried army of clay warriors.
One of the world's highest single-drop falls.
Two hundred and seventy-five waterfalls on the ArgentinaโBrazil border, with walkways to the lip of the Devilโs Throat.
The Parthenon and its temples on the rock above Athens โ the birthplace of democracy, best climbed at opening time.
Sacred red monolith at the desert heart.
Infobox