A digital painting using Gruppe in DAP of Folly Bridge, Oxford in 1896. The original, black and white, out of copyright image is from “Oxford: Brief Historical and Descriptive Notes” by Andrew Lang and was supplied by fromoldbooks.org
The bridge apparently stands at the site of the ford over which oxen could be driven across the Isis, the ancient name of the reach of the Thames between Folly Bridge and Iffley Lock. The first known stone bridge on the site was built by Robert d’Oilli in around 1085, but there was believed to be a wooden bridge in the time of Ethelred of Wessex. Remains of the Saxon structure may still be seen beneath the present bridge.
Until the late 17th century the bridge was known as South Bridge, and formed part of a long causeway known as Grandpont, which stretched along most of the line of Abingdon Road. In the 13th century, the alchemist Roger Bacon lived and worked at “Friar Bacon’s Study” which stood across the north end of the bridge until 1779, when it was removed to widen the road. Samuel Pepys visited Bacon’s study in 1669.
In 1369, when there was a grant of pontage on “Grauntpount”, the structure was said to be “so dangerous as to be well nigh impassable”.