Explainer: 10 slices of summer science
At sunrise on the summer solstice, druids, pagans and partygoers converge on a circle of stones in the English countryside to welcome the longest day of the year. The ritual at
Explainer: 10 slices of summer science
At sunrise on the summer solstice, druids, pagans and partygoers converge on a circle of stones in the English countryside to welcome the longest day of the year. The ritual at Stonehenge likely dates back thousands of years: Archaeologists estimate wooden posts and timbers were in place as early as 3100 B.C., although the monument's original purpose remains a mystery. One theory holds that it was a cemetery; another that it was a place of healing. Most archaeologists believe the large sarsen stones in the post-and-lintel formations seen in the background of this image served to mark th