The Altar Stone of Stonehenge: Origins and Mysteries Revealed

The Altar Stone of Stonehenge: A Journey Through Time

At the heart of the iconic Stonehenge, a remarkable circular monument dating back approximately 5,000 years, lies the Altar Stone. This six-ton, rectangular slab of red sandstone has captured the imagination of many, particularly in the context of Arthurian legend. According to these legends, the wizard Merlin was said to have magically transported the Altar Stone from Mount Killaurus in Ireland to its current location on Salisbury Plain, a chalk plateau in southern England. This fantastical journey was first chronicled around 1136 by Geoffrey of Monmouth, a Welsh cleric, in his historical narrative, Historia Regum Britanniae.

Over the centuries, the origins of the Altar Stone have been the subject of much speculation, with theories suggesting various locations from eastern Wales to the northern regions of England. However, a groundbreaking study published on Wednesday in the journal Nature has significantly altered our understanding of the stone’s provenance, proposing an even more extensive journey than previously believed.

In their research, scientists conducted a thorough analysis of the chemical composition and the ages of mineral grains found in two microscopic fragments of the Altar Stone. This meticulous examination pinpointed the stone’s source to the Orcadian Basin in northeast Scotland, an area encompassing Inverness, the Orkney Islands, and the Shetland Islands. To transport this megalith to the archaeological site in Wiltshire, it would have traveled an astonishing distance—at least 465 miles overland or more than 620 miles along the coastline if transported by sea.

Rob Ixer, a retired mineralogist and research fellow at University College London, who contributed to the study, expressed his astonishment: “This is a genuinely shocking result. The work prompts two important questions: How and why did the stone travel the length of Britain?”

Stonehenge itself is composed of two primary types of rocks: the massive sarsens and the smaller bluestones. The sarsens, which are large sandstone slabs, are naturally occurring in southern England and typically weigh around 20 tons each. These colossal stones were arranged in two concentric circles, with the inner configuration consisting of five trilithons—two upright stones topped by a horizontal lintel—of which three remain standing today.

In addition to the Altar Stone, the Stonehenge site features various other intriguing stones, including the bluestones, which researchers like Richard Bevins, who studies the origins of these stones, have traced back to locations such as north Pembrokeshire on the southwest coast of Wales. This ongoing research continues to unveil the mysteries surrounding one of history’s most famous archaeological sites.