The character and extent of archaeological remains associated with the loss of this vessel are presently unknown.

Event and Historical Information:
The PENRHYN CASTLE was described as both a smack and a sloop by the Court of Enquiry which looked into the loss. Measuring 48ft long x 15ft breadth x 8ft depth, the sloop was owned by Jones & Company and was commanded by John Jones. The sloop/smack was enroute from Aberporth to Milford Haven Harbour, when at 4am the lights of a steamer were seen on the starboard bow. The steamship, which proved to be the 250 tons GREAT WESTERN of Milford, captain Richard Guy, maintained her course until within three or four ship lengths of the sloop, then ported her helm and struck the sailing ship on the starboard side between the two after shrouds, sinking the sloop almost immediately 0.5miles south of St Ann's Head. As soon as possible the steamer lowered a boat which picked up the master and his brother, who was acting mate. The master, John Jones, expiring on board the steamer, whilst the sloop's boy unfortunately drowned. It was alleged by the steamer's officers that the sloop showed no lights and was only seen when they were 300 yards apart. The Court considered the evidence conclusive that the sloop was showing lights at the time of the casualty, and even if not, the steamer should have taken other action. The Court also found that her speed of 11 knots too great when rounding a headland, and that captain Guy should have kept clear of the sailing ship. His certificate was suspended for six months.

Sources include:
Larn and Larn Shipwreck Database 2002

Maritime Officer, RCAHMW, March 2008.