UC 18
Protected Area
Gouliot Caves and Headland, Sark
Why dive here
With 176+ marine species recorded in the area - including blue sharks, dolphins, dwarf minke whales, humpback whales and ocean sunfish (mola mola) - UC 18 offers some of Cornwall & Devon's richest wreck diving. Water ranges 10-18°C, warmest July, August, September.
The UC 18, a German submarine sunk in 1917 by the British sub chaser *Lady Olive*, rests upright at 52 meters, surprisingly intact given its fiery end. At 52.7 meters long, she’s a decent size for a single dive, with the conning tower still identifiable and providing a good orientation point. We’ve found her to be quite moody depending on the day; sometimes visibility allows for a full appreciation of her structure, other times you’re really relying on your torch to pick out the details of the hull, now draped in soft corals and sponges. This deep, open-water wreck is definitely one for experienced technical divers, offering a respectful peek into a piece of wartime history, now home to plump wrasse and curious conger eels.
Typical UC 18 Dive Profile
Illustrative profile based on site depth and type. Actual dive profiles vary - always follow your dive computer and training.
Safety Notes
Maximum depth 52m exceeds recreational limits (40m). Technical diving certification and equipment required.
Wreck site - avoid penetration without wreck diving certification. Watch for sharp metal and entanglement hazards.
Always perform a 3-minute safety stop at 5m before surfacing.
Nearest Dive Centres to UC 18
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Conditions
Ocean conditions, forecast and tides for UC 18
UC 18 Ocean Conditions
Monthly averages for UC 18, sourced from Open-Meteo marine data - nearest station: Open-Meteo marine grid (50.44, -2.73) (3km away)
October Averages
Sea Temperature
17°C
62°F · Range: 15.1–17.5°C
Air Temperature
13°C
56°F
Wind Speed
8.14 m/s
15.8 knots
Atmospheric Pressure
1011 hPa
Based on 4 years of monitoring data · Data sources: Open-Meteo marine data
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