Rock-cut cave complex filled with ancient Buddhist artwork.

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.

Life and death are on parade at the most reliably perilous site of “the Great Migration.”

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

An old Dutch lightvessel is now stuck in a dock near the mouth of the Suriname River.

Though dynamited and defaced, the statue still stands outside the law courts in Georgetown, Guyana.

The largest market in Guyana, designed and built by the Edge Moor Iron Company of Delaware.

Georgetown’s most impressive building is also one of the tallest wooden churches in the world.

The world's widest single drop waterfall, and the two men who legend says went over its edge in a boat.

A popular European tradition makes its way to the states on one of America's most famous bridges.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

Eighty million natural history specimens call this gargantuan museum home.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Only a handful of these gorgeous historic waterwheels remain but even those are in danger from local unrest.

Amid the rubble of Aleppo's Old Quarter, part of a historic market has been restored and re-opened.

Ruins of the Crusaders' headquarters.

Mysterious lost empire of the Silk Road.