hill fort may have been abandoned by this time, as Roman archaeological finds uncovered during excavation of the site in 1986 all overlaid native finds. The tower was thought to have been constructed out of timber during the Flavian period, with a later tower being constructed out of stone during the reign of Emperor Antoninus Pius. Finds including Roman coins and pottery have suggested that some of the house platforms were again in use in the 2nd to 4th century. There is some evidence that prehistoric peoples regarded the Eildon Hills as a holy place and scholars believe they may have been a place of ceremonial gatherings. There are several holy springs around the base of the hills, now dedicated to Christian saints, but probably originally sacred to Celtic deities. They were once known as Eldune, derived from the 12th-century Simeon of Durham who referred to them as . The final part of the word is Old English dun, meaning a rounded hill, while the first part has been variously etymologized as Brittonic eil (referring to a fenced enclosure) or Old English ǣled ("fire") or ǣlǣte ("empty place").<ref>{{cite web|last=James|first=Alan|title=The Brittonic Language in the Old North: A Guide to the Place-Name Evidence, Volume 2 (Guide to the Elements)|year=2019|url=https://spns.org.uk/wp-content/uploads/2019/03/Alan_James_Brittonic_Language_in_the_Old_North_BLITON_Volume_II_Dictionary_2019_Edition.pdf|format=PDF|website=Spns.org.uk}}</ref> Formation It is possible that the hills were formed deep beneath the Earth's surface as ancient laccoliths. In folklore Eildon is said to be a "hollow hill", and is mentioned in the legend of Thomas the Rhymer. Some believe Thomas went under the hill itself, and certainly part of the ballad occurs in the vicinity. Sir Walter Scott tells the tale of a horse dealer who is paid in "ancient coin" by an elderly buyer in old-fashioned dress and taken inside the hill at night. A host of armed knights lie asleep at their horses' feet; their sleeping leader is King Arthur. Shown a horn and a sword, in confusion the dealer blows the horn: the men begin to awake and a loud voice indicates that he has been proved a coward for not seizing the sword first. A whirlwind ejects him from the chamber and outside he tells his story to some shepherds before dropping dead of exhaustion. Scott identifies the elderly man as Thomas the Rhymer. Another legend concerns the Eildon Tree Stone, a large moss-covered boulder near Melrose, marking the spot where the Fairy Queen led Thomas into her realms