"If you want to grace the burial-place of these men with some lasting monument," replied Merlin, "send for the Giants' Ring which is on Mount Killaraus in Ireland. In that place there is a stone construction which no man of this period could ever erect, unless he combined great skill and artistry. The stones are enormous and no one alive is strong enough to move them. If they are placed in position round this site, in the way in which they are erected over there, they will stand forever."

At these words of Merlin's Aurelius burst out laughing. "How can such large stones be moved from so far-distant a country? he asked, "It is hardly as if Britain itself is lacking in stones big enough for the job!" "Try not to laugh in a foolish way, your Majesty," answered Merlin. "What I am suggesting has nothing ludicrous about it. These stones are connected with certain secret religious rites and they have various properties which are medicinally important. Many years ago the Giants transported them from the remotest confines of Africa and set them up in Ireland at a time when they inhabited that country. Their plan was that, whenever they felt ill, baths should be prepared at the foot of the stones; for they used to pour water over them and to run this water into baths in which their sick were cured. What is more, they mixed the water with herbal concotions and so healed their wounds. There is not a single stone among them which hasn't some medicinal virtue." [VIII.12]

STONEHENGE is introduced in the Historia as a monument to the Britons killed by the treachery of Hengest and laid to rest at MOUNT AMBRIUS , near SALISBURY. Merlin convinces Aurelius and his men to go to Ireland to fetch the Giants' Ring. They have to fight the Irish leader Gillomanius. Having defeated the Irish, they come to Mount Killaurus, but are unable to move the stones:

... they all set to work with every conceivable kind of mechanism and strove their hardest to take the Ring down. They rigged up hawsers and ropes and they propped up scaling-ladders, each preparing what he thought most useful, but none of these things advanced them an inch. When he saw what a mess they were making of it, Merlin burst out laughing. He placed in position all the gear which he considered necessary and dismantled the stones more easily than you could ever believe. Once he had pulled them down, he had them carried to the ships and stored on board, and they all set sail once more for Britain with joy in their hearts.... Aurelius ordered Merlin to erect round the burial-place the stones which he had brought from Ireland. Merlin obeyed the King's orders and put the stones up in a circle round the sepulchre, in exactly the same way as they had been arranged on Mount Killaraus in Ireland, thus proving that his artistry was worth more than any brute strength. [VIII.12]

The site becomes a royal burial-place:

After this great undertaking, Uther set out for Winchester with all possible speed. Messengers who came to meet him told him of the King's death, saying that Aurelius was soon to be buried by the bishops of the country near the monastery of Ambrius and inside the Giants' Ring. [VIII.16]

As soon as the death of the King [Uther] was made known, the bishops of the land came with their clergy and bore his body to the monastery of Ambrius and buried it with royal honours at the side of Aurelius Ambrosius, inside the Giants' Ring. [VIII.24]

Constantine discovered him and slew him without mercy, beside the altar there. Four years later he was himself struck down by the vengeance of God. They buried him by the side of Utherpendragon, within the circle of stones called Stonehenge in the English language, which had been built with such wonderful skill not far from Salisbury. [XI.4]

The last reference to Stonehenge recorded above gives the English form of the name, Stanheng. Henry of Huntingdon contains the earliest record of Stonehenge but he did not connect the site with the battle and memorial: these are apparently Geoffrey's innovation (Tatlock, pp. 40-41). The English Heritage information site on Stonehenge records the history of the site: Geoffrey's version is not mentioned.