Nennius, a 9th-century historian, mentions a "Hot Lake" in the land of the Hwicce along the River Severn, and adds "It is surrounded by a wall, made of brick and stone, and men may go there to bathe at any time, and every man can have the kind of bath he likes.
=== Post-rimski čas in srednji vek ===Bath bi lahko bilo prizorišče bitke pri Mons Badonicus (ok. leta 500), v kateri naj bi kralj Arthur premagal Anglosase.