earthwork

This great tomb-temple dates from 3200 BCE, a thousand years before Stonehenge was built. It is astronomically aligned and includes some fascinating ancient rock art.

The center of Mississipian Indian culture from 900 to 1300, Cahokia was the largest pre-Columbian community in North America and produced several ritual earthwork mounds. The site is located in Illinois, just across the state border from St. Louis.

This man-made earthwork in the shape of a long, uncoiling serpent a quarter of a mile long was created between 1000 and 1500 CE for unknown purposes. It is now protected in a state park in Ohio.

Dating from about 3000 BC, Knowth consists of a large central mound surrounded by several smaller ones. It is especially important for its rich collection of megalithic art.

Teamhair na Rí ("Hill of the King") is a stretch of grassy landscape that has played a central role in Ireland's history, legend, and folklore. It contains several ancient burial mounds and other earthworks.

Located near Avebury, this is the largest prehistoric man-made mound in Europe. It was created around 2660 BC and stands 130 feet high. Its purpose remains mysterious.

These two prehistoric man-made mounds add a bit of mystery to Krakow's skyline. Their purpose remains unknown, but both are perfectly astronomically aligned with the sunrises of important Celtic days.

This intriguing chalk figure of a club-wielding naked man may be a drawing of a fertility god, Hercules... or Oliver Cromwell. No one knows exactly when or why it was made.

Dowth is the least known of three passage tombs in Brú na Bóinne, Ireland. Unlike its neighbors, Dowth has not yet been thoroughly excavated and is currently closed to visitors, but it can be viewed from the road.