The Magna Britannica (published in 1822) reported that “the Quay, which was constructed in 1663, belongs to the corporation,” thus providing a date that has found its way into other later publications (e.g.White’s Directory for 1850). More properly, it seems that 1663 was the year in which the building of a new quay was ordered, the finance to come from gifts, but supplemented by a fine on the bridge and town lands. This new quay appears to be an extension to the Established Quay. At what point the building got under way, and when the new quay was first used remains uncertain.

Borough documents of 1671 mention two quays The Kaye (possibly the Established Quay) and Strand Kaye (which was probably a quay on that part of Potters Pill where boats were stranded at low tide, an area still known as The Strand). Yet alternative possibilities cannot be ruled out, The Kaye may referred to The Key on the west whilst Strand Kaye could refer to the Established Key (their is evidence from 1717 that one benefit of the later southward extension of the Established Quay was the access to deeper water that it provided, so boats moored at the older part of the Established Quay may well have been stranded at low tide).