Three dredged channels some 240m long and 17m wide provides access to a large quarry, in which the channels appears to interconnect. The easternmost channel is theh most straightforward to decipher. It doglegs to enter the quarry floor and warping/turning area. The dock is a turn to the south. A short dock has been cut into the eastern side of the channel, possibly to allow vessel's to pass (SN03020603). The central channel appears to serve two quarries; the first has a quay close to the northern side of its entrance (SN02950603); the second quarry provides a dock some 48m x 27m with a quay a turn to the south and on the western side. The westernmost channel opens into the largest worked out area. Modern aerial photography provides the best clues from the channel cuts for where one of the dock and warping areas was formerly situated - e.g. at the furthest southern end SN02970586 closest to Williamston Park/Ship Public House (NPRN 518824).

Williamston Park Quarry was a source of limestone from around the late C18th and activity continued until the early C20th. The result of this industry is a peninsula deeply cut by channels created to allow boats to enter and load up with stone. These cuttings now survive as tidal creeks some still opening out onto old quarry workings which have become salt marsh. Some of the cuttings have silted up or dried out and been invaded by scrub. A small area of channels at the south have been reclaimed and turned into pasture. Between most of the channels are none too obvious former spoil tips, very overgrown, but there are one or two surviving quarried rock faces as well as natural limestone outcrops.
According to Moore Colyer the stone from this quarry was in great demand for agricultural use (lime burning) as well as furnishing building stone for Milford docks and military works on Milford Haven. Accessibility of the raw material was a major factor in its exploitationin this particular area.

Sources include:
NAW aerial photography 2006-9
OS 1st edition 25in mapping
J Latham, Williamston Park, Report for NT, 1987.

Maritime Officer, RCAHMW, May 2012.