The Great Hall, St Martins Road/Oak Street Nowich.
A medieval traders hall, all but forgotten, also one of the few survivors of the blitz and the clearings on the whole of Oak Street.
The building dates back to at least 1480, and features the remains of an Oriel window, split by the addition of a second floor and the addition of weavers windows. The hall has had many owners, largely weavers at least until the 18th century. This is entirely consistent with various bits and bobs I've read that indicate that the Northern bank of the wensum shows evidence of being used by dyers, proof of which exist in the continuation of names, such as Dyers Yard 200 yards away towards the city. This also would have been in a prime trading spot, just inside the city wall near St Martin's Gate.