Why was Stonehenge built?

Stonehenge may be the most famous of all megaliths. Various theories attribute its construction to Druids, Merlin, and even aliens. Although it is clear that Stonehenge was deliberately constructed, no one really knows why. This analysis focuses on the original purpose for which it was built, irrespective of what its functions may have been after it was constructed.

The evidence doesn't fit neatly with any of the competing hypotheses. The construction of Stonehenge took place about 5,000 years ago, and there's little information about similar structures at the time. Therefore, it is possible that the true hypothesis has not yet been suggested or considered. However, among the hypotheses known today, the most likely explanation is that Stonehenge was built as a place of sun worship.

The alignment with the sun and the burials at the site suggest that Stonehenge was either a place of sun worship that included a burial ground or a (religious) burial site for people with strong ties to the sun and solstice. The graves and the sheer magnitude of such a project are more difficult to account for under the "Calendar" hypothesis. While there is peripheral evidence that may associate Stonehenge with healing (such as the origin of the bluestones, and skeletons that had medical problems), projects of this magnitude are without precedent and unlikely for healing alone.

The hypothesis that Stonehenge was built by Druids (suggested in the 17th century), is rejected outright (and not analyzed) due to the abundance of evidence that Stonehenge was completed by 1500 BC, while the Druids only arrived in England around the year 600.

An additional mystery analyzed is whether the bluestones from Preseli reached the Stonehenge area through glacier flow, or were manually transported. The conclusion finds glacier flow to be very likely, mostly due to the large variety of bluestone sources - since deliberate mining probably would have focused on one or two quarries and not multiple quarry sites.