647-ton, UBIII-class German navy submarine, built 1917. 183ft x 19ft. From Zeebrugge to attack shipping in Channel. Position: 50 29.37N; 00 58.20W. Depth: 28m. Sunk: 2 December, 1917, by striking a mine. Bottomed with flooded stern in 30m, 2 miles south of Owers Lightship. A rescue attempt failed. 27 of 34 drowned. Wreck has moved more than 12 miles since sinking. Diving: Broken in two just aft of conning tower, which is also badly damaged. Highest point is a gun, which points towards surface, ammunition lying around. Main hatch open to control room. Parts of gun and bridge telegraph have been removed. Launch: Bembridge, Portsmouth.