Serpent Mound
A huge earthwork snake winds across a ridge in Ohio, its head pointing towards the midsummer sunset, and no one agrees who built it.
What was reported
Serpent Mound is an earthwork in the shape of a snake, about 400 metres long and around a metre high, lying on a plateau in Adams County, Ohio. Its body coils across the ridge, and its open jaws seem to hold an oval shape.
Its head lines up with the sunset on the summer solstice, and some argue that its coils point to other events in the Sun's and Moon's cycles.
Explanations offered
Radiocarbon dates have pointed to two different cultures: the Adena, around 300 BC, and the Fort Ancient culture, around 1070 AD. It may have been built by one and rebuilt by the other. Some have suggested it was inspired by Halley's Comet of 1066, though there's no way to confirm that.
- When
- Built over 900 years ago
- Where
- Adams County, Ohio, USA
- Witnesses
- Archaeologists
- Status
- Disputed
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.