Europe's largest prehistoric mound – burial site of a legendary king?

This Scottish burial tomb once held hundreds of ancient eagle bones.

Thanks to both terrific preservation and historic vandalism this ancient site is known as the "Heart of Neolithic Orkney."

This beautiful ancient site is dotted with perforated sandstone pillars considered sacred by some Native American groups.

This state park was once an important Native American cermonial center.

The remains of a enormous earthen figure of unknown origins cuts across a rural Wisconsin road.

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.

A collection of huge Pre-Colombian structures in Alabama.

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

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

A well-preserved Ancestral Puebloan ruin tucked beneath a desert cliff.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

This Corsican Neolithic site is full of pre-Roman megalithic structures that may or may not be penises.

Besieged by war, this castle ruin has crumbled into a peaceful picnic spot.

These ruins of a pre-Columbian cliff village are among the most beautiful and well preserved in New Mexico.

The first archaeological site discovered by aerial photography.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

This ancient Irish religious site is covered in ancient carvings, many of which have barely aged.

Just another ancient, mysterious Irish stone circle.

If they push on just the right spot, even the weakest person can move this titanic boulder.

An aluminum skeleton brings Chinese mythology to the French shore.

Famously misunderstood wonder of the ancient world

One of the great treasures of Neolithic art lies within this carefully constructed pile of rocks.