In the 1st century CE the Roman army built the massive fort of Trimontium at Newstead, named after the three peaks, at the foot of the hill on the bank of the River Tweed. In association with this fort they constructed a signal tower with a tiled roof in a 15 m diameter enclosure built on the summit of Eildon North Hill. The 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.