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Mystery wreck

Mystery wreck
LOCATION: -5.4, 52.72

The multibeam scan and model show an unidentified wreck previously thought to be the ROSE MARIE. The collier ROSE MARIE was torpedoed and sunk without warning on 5 January 1918 by U 61 when 13 miles southeast of the North Arklow light vessel. One life was lost.

A ROSE by any other name…?

This wreck was located by HMS BEAGLE in June 1981 in the area where the ROSE MARIE was reported to have sunk.

Technical specifications for the ROSE MARIE give a length of 280ft (85m), whereas this wreck appears to be around 260ft (79-80m) in length.

The deck layout of the wreck suggests that the bridge was more towards the stern. Whereas in this photographs of the ROSE MARIE’s sister ship, the bridge is in the centre of the ship.

We invite you to explore the 3D model and see if you can identify any other features which might help us to decide whether indeed this is, or is not, the ROSE MARIE.

Vital to the war effort

We included the ROSE MARIE in our surveys because she illustrates the vital importance of Welsh steam coal to the Royal Navy. She was chartered to operate as Admiralty Collier Number 1845 and, for the six months before her loss, she had been conveying coal from Grangemouth, Immingham and Barry Dock to the naval base at Scapa Flow. It was from there that the Grand Fleet sailed in May 1916 to engage the German High Seas Fleet at the Battle of Jutland.

As part of the Armistice, seventy-four ships of the German High Seas Fleet arrived in Scapa Flow for internment. Their Commanding Officer, Rear-Admiral Ludwig von Reuter, would give the order to scuttle the ships in June 1919.

The ROSE MARIE was a 2,220-ton, defensively-armed steam collier built in 1916 in Sunderland for the Rodney Steamship Company in Newcastle. ROSE MARIE was torpedoed and sunk without warning on 5 January 1918 by U 61 when she was 13 miles southeast of the North Arklow light vessel. She had been returning from Scapa Flow to Barry ‘in ballast’. She had probably been delivering Welsh steam-coal to the British fleet of warships stationed in the north of Scotland at Scapa Flow.

One life was lost – Royal Naval Volunteer Reservist Edgar Treharne aged 22 from Dillwyn Street, Llanelli. His body was not recovered. Edgar had been serving in the RNVR as a gunner on armed merchant ships since September 1916 and had previously survived the sinking of the SS BENHEATHER in April 1917. He had been working at the Burry Tinplate Works, Llanelli.

Article about Edgar Treharne in the South Wales Weekly Post, 16 Feb 1918. Source: Welsh Newspapers Online.

The mystery of the fate of U 61

U 61 disappeared two months after sinking the ROSE MARIE, in late March 1918. U 61 began its final patrol on 14 March 1918, when she sailed from Heligoland for the Irish Sea. Three days later, it rendezvoused west of the Orkneys with U 101, which had requested via radio that it transferred a replacement engine part. U 61 reached its operating area, torpedoing and sinking the British passenger steamer ETONIAN early on 23 March off the Old Head of Kinsale. After this there was no further contact with U 61.

U 61 had sunk 30 ships in the previous twelve months under the command of Victor Dieckmann. It must be assumed that he died with his crew of 35 men when U 61 sunk. However, it will probably take the discovery of U 61’s wreck to determine what happened to Victor Dieckmann and his crew. He was 30 years old. It has been estimated that up to 50 % of U-boat crews lost their lives in the First World War.

Photograph of sister ship ALICE MARIE. Source:

Colliers supplying Welsh steam-coal to Scapa Flow

The Royal Navy’s Grand Fleet was based at Scapa Flow in Orkney during the First World War. Although the Royal Navy was gradually changing over to oil fuel at that time, most warships were still coal-fired. The semi-bituminous ‘Admiralty steam-coal’, preferred by the Royal Navy was only mined at 40 collieries in parts of the South Wales coal fields. Each warship required roughly 1,000 tons of coal, so replenishing the fleet was a huge operation involving ships and trains (the ‘Jellicoe Specials’).

Coal-carrying ships (colliers) made the 14-day round trip from Cardiff and other south Wales ports to Scapa Flow. This meant that many were in transit at any one time and vulnerable to U-boat attack. 31 colliers were sunk in 1915 and 119 in 1917, with most of these carrying coal from the south Wales collieries.

Sources:ALICE MARIE.’ Wear Built Ships SS RT. 2019. Web.

Davies, J. D. 2013. Britannia’s Dragon, The History Press.

‘Llanelly Gunner Missing.’ South Wales Weekly Post. 16 Feb. 1918. p.1.

‘ROSE MARIE.’ Ships hit during WWI. Uboat.Net. 1995-2018. Web.

‘ROSE MARIE.’ Wear Built Ships SS RT. 2019. Web.

‘U 61.’ WWI U-boats. Uboat.Net. 1995-2018. Web.