Stonehenge's central rock came from Scotland — raising questions about how it got there

Scientists say they’ve cracked a secret of the 6-ton rock at the center of Stonehenge — a discovery that only deepens the site’s mystery. The ancient monument’s “altar stone,” a sandstone rock at its center, likely originated in present-day Scotland, according to a study published Wednesday in the journal Nature. That means it was hauled more than 450 miles to southern England — significantly farther than any other stone at Stonehenge with known origins. The finding raises profound questions. The researchers suspect the altar stone was installed about 4,500 years...