This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

For centuries young Thai men used this Giant Swing as a slingshot to heaven.

Thailand's distressed elephants find peace at this Chiang Mai sanctuary.

The headquarters of the Mahanikai school of Buddhism, Thailand's largest monastic order.

This sandstone mansion was the home of two of Oregon's most important pioneers.

A massive sea stack famous for its appearance in The Goonies.

The magic's in the hole!

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

Also known as the Square Colosseum, this building is a prime example of fascist-era rationalist architecture.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

The final resting place of the poets Shelley and Keats.

2300-year-old Roman road connecting the empire.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Like Mars, but much closer.

This abstract roadside poultry was saved from demolition by outraged drivers and pilots.

The statues commemorate the legendary mass killing of escaped circus monkeys.