Fresh wooden posts have been added to ancient holes to recreate a primitive henge clock.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

An extraordinarily ornate museum in San Diego holds wondrous anthropological treasures.

America's most famous piece of self-built architecture.

The original vault that held the president's remains still stands, empty, not far from where he was finally buried.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

The longest and widest floating bridge in the world.

The four tall pillars once marked the entrance of the historic Seattle church that fought for women's suffrage and civil rights.

A beautiful footbridge with over 2,000 glass sculptures along the walls and ceiling.

This old residential building was once the largest flour mill in the world.

These crudely shaped folk giants may be the the second most photographed statues in the U.S.

A bronze statue on a downtown corner honors Minneapolis's favorite career gal.

When flour explodes, it's not a pretty sight.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

This ancient trail climbs the mountain where a Latin League cult worshipped Jupiter, its main deity.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

The remains of an ancient Roman teenager are memorialized at the base of a modern London landmark.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.