The remains of what was, not so long ago, the world's largest city.

This complex of vertically-excavated Buddhist, Jain, and Hindu monolithic temples in India's Maharashtra providence illustrates a spirit of tolerance characteristic of ancient India.

Half-size replica of the Taj Mahal.

This restaurant is proud to be built atop a burial ground.

A nearly unconquerable island-fort in the Indian Ocean.

An extraordinary "City of Caves" carved from solid stone.

A centuries-old lookout post still sits atop a natural stone spire.

World's most expensive home.

Rock-cut cave complex filled with ancient Buddhist artwork.

A centuries-old fortress city lies in ruin.

One of the oldest churches in Romania is believed to have been built on the site of a pagan temple.

An old town theater converted into a celebration of the hobo legacy.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

Modern-day cave dwellers carve elaborate homes out of volcanic debris.