SS San Wilfrido was a steam-powered British tanker that was launched in February 1914 and sunk by a German mine less than six months later. Armstrong, Whitworth & Co Ltd built her on the River Tyne for the Eagle Oil Transport Co Ltd. San Wilfrido struck the mine in the North Sea on 3 August 1914, one day before Britain declared war on Germany. She was Britain's first naval loss of the First World War. This was the first of two Eagle Oil tankers to be called San Wilfrido. The second was the Empire ship , which Eagle Oil bought and renamed Sain Wilfrido in 1946. Building Armstrong, Whitworth & Co Ltd built San Wilfrido at Low Walker as yard number 856. She was launched on 11February 1914 and completed in April 1914. San Wilfrido was the third of four sister ships. In 1913 Armstrong Whitworth built San Urbano and Palmers Shipbuilding and Iron Company built San Valerio. In 1914 Palmer's launched San Zeferino the day after Armstrong, Whitworth launched San Wilfrido. San Wilfrido was long, with a beam of and a depth of . Her tonnages were , and . She had a single screw, powered by a quadruple expansion engine built by the Wallsend Slipway & Engineering Company Ltd, Wallsend. It was rated at 554 nhp and gave San Wilfrido a speed of . San Wilfridos UK official number was 136658 and her code letters were JFHC. History San Wilfrido made trips with usually 8,000 tonnes of oil out of her tonnage of 9,000. The ship was sunk just four months after her completion. Sinking On 3 August 1914 San Wilfrido was sailing from Hamburg to Portland in ballast. The trip was expected to take two and a half days, after which she would sail for New Orleans. While navigating the Elbe about eight miles above Brunsbüttel she was given permission to proceed until Cuxhaven at the mouth of the North Sea. No pilot vessel was available to take her through the minefield at Cuxhaven so she tried to proceed on her own along the usual channel. Tugboat men of the harbour tried to warn San Wilfrido'''s master of the danger by shouting. The master then tried to evade the mines by attempting to go full speed astern. However, at about 4 p.m., a strong ebb tide carried San Wilfrido into the mines. Three explosions followed and crippled