Submarine · 1918–1918 · Orkney, United Kingdom
SM UB-116
Also known as UB-116, UB116.
On 28 October 1918, with the Armistice barely a fortnight away, UB-116 attempted one of the war's most audacious submarine operations: a solo penetration of Scapa Flow through the mined entrance at Hoxa Sound to attack the British Grand Fleet at anchor. She never made it.
British hydrophone operators tracked her approach and detonated a remote-controlled mine that killed all 34 crew — the last U-boat lost in the First World War. Raised in 1919, she broke free and sank again at the mouth of Pan Hope Bay; a controlled explosion later dealt with her remaining live torpedoes, and the blast left her barely recognisable as a submarine.
What remains is a scattered field of torn steel and bent piping in 26 to 32 metres, with the conning tower standing as the only clearly identifiable feature. Orientation is challenging, but the story gives every twisted plate its weight. This is the physical full stop at the end of the U-boat war.
- Type
- SubmarineGerman
- Year built
- 1918Blohm & Voss, Hamburg
- Lost
- October 28th, 1918Mined
- Casualties
- 34World War I
- Length
- 55.3 m5.8 m beam
- Depth
- 26–32 m
- Location
- Orkney, United KingdomScapa Flow
0 of 7 facts above are cited in Sources below.
Deeper than 100 of the 185 wrecks on the map with a recorded depth.
History and LossLost October 28th, 1918 · Mined · World War I · Orkney, United Kingdom.
The last U-boat sunk in the First World War never even saw her target. On 28 October 1918 — just two weeks before the Armistice — UB-116 attempted to slip into Scapa Flow through Hoxa Sound to attack British capital ships at anchor. What her crew did not know was that the defences had been recently upgraded with hydrophone-triggered mines.
Shore operators detected the submarine's approach and detonated a mine directly beneath her. All 34 crew were killed instantly. The wreck was raised in 1919 but foundered at the mouth of Pan Hope Bay during the tow. Live torpedoes were later dealt with by controlled explosion.
Today UB-116 lies at 26 to 32 metres on a sandy seabed, broken but identifiable — conning tower, torpedo tubes, and hull sections visible.
Built 1918 by Blohm & Voss, Hamburg; 0 years in service, also recorded as UB-116 and UB116. Lost October 28th, 1918, mined during World War I.
Condition of the WreckScattered, in 26–32 m.
Intactness
Very broken up. Scattered remains form a tangled mass of torn metal and bent piping bearing little resemblance to a submarine. Conning tower is one of the few remaining identifiable features.
Notable Features
- Conning tower — main identifiable feature
- Last U-boat sunk in WWI
- Scattered submarine remains
Regulations and RestrictionsProtected site · Permit required.
This is a legally protected site. A permit is required to dive this site. Diving permit required from Orkney Islands Council Harbours department.
Additional Details14 further fields held for this wreck and not shown above.
- Nationality
- German
- Flag
- German Empire
- Builder
- Blohm & Voss, Hamburg
- Propulsion
- Diesel/electric
- Loss date
- October 28th, 1918
- Conflict / event
- World War I
- Latitude
- 58.83° N
- Longitude
- 3.07° W
- Water body
- Scapa Flow
- Restrictions
- Diving permit required from Orkney Islands Council Harbours department
- War grave
- No
- Protected
- Yes
- Permit required
- Yes
- Condition
- Scattered
Sources and VerificationEvery cited fact on this page traces to a published source.
- Scapa Flow Dive Sitesscapa-flow.co.uk · Secondary source1 fact
- Scapa Flow Wrecksscapaflowwrecks.com · Secondary source1 fact
- Wikipediaen.wikipedia.org · Background reading1 fact
Background reading is listed for context and is not counted as a citation for the facts above.
Licences and credits for the open data used on this site are on the Attribution page.
Frequently Asked Questions
What is the SM UB-116?
SM UB-116 is the wreck of a submarine, off Orkney, United Kingdom, at 32 metres. SM UB-116 struck a mine in 1918.
How deep is the SM UB-116?
SM UB-116 lies at 26 to 32 metres, Mouth of Pan Hope Bay, east side of Flotta, Scapa Flow.
How did the SM UB-116 sink?
SM UB-116 struck a mine on October 28th, 1918 during World War I, off Orkney, United Kingdom. 34 people lost their lives.
Is the SM UB-116 protected?
Yes. SM UB-116 is recorded as a legally protected site.