Arfon, built in 1908 in Goole as a steam-trawler, was later refitted for the Royal Navy and worked out of Portland for three of the war-years, sweeping mines laid by German U-boats along the inshore shipping lanes off Dorset.

The vessel sank rapidly off St Adhelm’s Head near Swanage after striking a mine in 1917. Last year it was given special protection by the Department for Culture Media & Sport on the advice of Historic England (HE), as reported on Divernet.

The commemoration ceremony was set to include the ship’s recovered and restored steam-whistle being sounded for the first time since the sinking, when it signalled the code for “mine”. The names of the 10 crew who died were to be read out along with those of the three survivors.

The descendants were then to visit St Aldhelm’s Head for the unveiling of an information board about the ship, which was discovered by diver Martin Jones in 2013.

“By pure luck, while on a diving trip to another wreck I spotted an anomaly on the seabed,” said Jones, now the Arfon licensee. “I marked the position on the GPS, but it was not until 2014 that my son Bryan dived the site for the first time.”

It was research by Bryan Jones and local maritime historian Dave Wendes that identified the long-lost wreck. Lying in a depression at 43m, it is exceptionally well-preserved, with mine-sweeping gear, deck-gun, portholes and engine-room still intact.

To tie in with the commemoration ceremony, the Maritime Archaeological Trust (MAT) has launched an HE-funded online dive-trail. Derived from more than 10,000 images collected by MAT divers in 2016 and early 2017, it features a guided 3D tour of the wreck that includes interactive information points, audio and videos, images, animations and 360-degree panoramas. It can be found here.

MAT plans to “virtually restore” the steam-whistle and other raised artefacts to the wreck on the commemorative website, and to carry out further dives in 2017 to add to the virtual tour for its Forgotten Wrecks of the First World War project.

“I have found it enormously rewarding sharing the information with the descendants of three of the crew, and look forward to meeting them all on the centenary commemoration,” said Martin Jones.

“We would like to thank HE and MAT for the enormous amount of work that they have contributed to this project and we hope the Arfon will be left in its pristine condition and respected for its rarity and historical value for many years to come."

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