A GERMAN U-boat that was sunk off Bardsey Island on Christmas Day 1917 has been pictured for the first time using sonar imaging.

U-87 went down off the north Wales coast when it was rammed by an escort vessel hours after sinking a steamship.

It was thought that the submarine was in two pieces, but a joint project by The Royal Commission on the Ancient and Historical Monuments of Wales and Bangor University to survey shipwrecks along the Welsh coast, has revealed the vessel is in one piece at the bottom of the sea.

A survey boat carrying the sonar equipment has generated an image of the German U-87, which went to the seabed with more than 40 crew on board, after it was hit by HMS Buttercup.

It had been a busy Christmas Day for the crew of U-87.

The submarine attacked a convoy at 2.45pm, torpedoing steamship AGBERI which destroyed all the portside lifeboats amidships. The 54 crew members and 9 passengers were able to get away on the ship’s other lifeboats.

The wreck of the AGBERI sits upright on the seabed 18 miles northwest of Bardsey Island and has a length of over 120m and a height of 19m.

Its midships superstructure is reported to be intact.

During the attack, U-87 was rammed by the sloop Buttercup, but still remained a threat.

It was sighted shortly after by HM Patrol Boat 56 which dropped two depth charges alongside. The U-boat was forced to the surface.

Dr Michael James Roberts, from Bangor University’s Centre for Applied Marine Sciences, described the find as a “moving and thought-provoking experience” when the sonar image appeared on the computer screen for the first time.

“Regardless of who these men were, they were only doing their job,” he said.

A conference on the U-Boat Project 1914–18, Commemorating the Welsh Experience of The Great War, will be held at Sea Pater Hall, Pembroke Dock on 3 and 4 November.

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