Caerleon's Market Hall was built c.1622, as attested by the survey of Caerleon Manor for that year, which states that a local merchant, Phillip Hughes, held land on which a `hansume and convenient market house? was to be built. The finished structure comprised a loft or chamber, mounted upon four freestone columns, believed to be of Roman, or part-Roman, origin. The chamber, which served also as a court room and a place of general assembly, was reached via a stairway from the street. The area below was reserved for market stalls.
By 1848 the building had fallen into such a poor state of repair that when its owner, Sir Digby Mackworth, proposed renovating it to be the community's museum, local residents paid to lease the land from Mackworth in order that it may `remain an open space forever?. The building was therefore torn down; materials from the Market Hall were then incorporated into the Roman Legionary Museum (NPRN 31953) built in 1850, including the four Roman columns, which supported its basement.

Source: Kennerly, E., `Caerleon Market Hall?, Gwent Local History 37, 1974

K Steele, RCAHMW, 30 December 2008