CAIRNDHU - Cornwall & Devon

The Cairndhu, a substantial steamship, lies broken but still impressive at 23 metres. We often hit this one when the weather pushes us away from the exposed coast, and it rarely disappoints. She went down fast in 1917, torpedoed, and the impact left her in two main sections, but there’s enough structure to keep you busy. Our favourite part is poking around the stern, where the prop shaft leads you towards the impressive triple expansion engine. You’ll find conger eels tucked into every dark crevice, sometimes a foot thick. Visibility can be hit or miss, typical for the English Channel, but even in murkier conditions, the sheer scale of the wreck emerges slowly, dramatically. Bring a good torch and take your time; the cargo holds are full of brass and porcelain, reminders of her final journey. It’s a proper historical dive, perfect for those who like their wrecks with a bit of mystery and plenty of nooks to explore.

Location
Cornwall & Devon, United Kingdom, Mediterranean & Europe
Coordinates
50.625380, -0.439133
Type
wreck
Maximum Depth
23m

Wreck History - CAIRNDHU

Year Sunk
1917
Vessel Type
cargo ship
Cause
torpedo

The SS Cairndhu was a British steamship built in 1911 for the Cairn Line. Like so many other merchant vessels, it was pressed into service during the First World War, braving the perilous, U-boat-infested waters to transport essential supplies. On April 15, 1917, while on a voyage from South Shields to Gibraltar carrying a cargo of coal, its luck ran out. The Cairndhu was spotted by the German submarine SM UB-40, commanded by Oberleutnant zur See Hans Howaldt. A single torpedo sealed the ship's fate, sending it to the bottom of the English Channel.

Located in 23 meters of water, the Cairndhu is now a popular and fascinating wreck dive off the coast of Cornwall. The wreck is significantly broken up, a testament to the force of the torpedo and over a century spent on the seabed. Despite this, its main features, including the boilers and the triple-expansion engine, are still clearly visible and provide a focal point for the dive. The scattered plates and ribs of the hull have created an ideal artificial reef, attracting an abundance of marine life. Divers can expect to see schools of bib, pollack, and wrasse, as well as conger eels and lobsters seeking shelter in the wreckage.

Marine Protected Area: Kingmere

Best Time to Dive in Cornwall & Devon

The warmest water temperatures in Cornwall & Devon occur in January, averaging 9.6°C. The coolest conditions are in December at 9.6°C.

Monthly Water Temperatures

  • January: 9.6°C (air: 7.3°C)
  • February: 9.6°C (air: 8.4°C)
  • March: 9.6°C (air: 8.6°C)
  • April: 9.6°C (air: 10.1°C)
  • May: 9.6°C (air: 12.6°C)
  • June: 9.6°C (air: 15.2°C)
  • July: 9.6°C (air: 16.6°C)
  • August: 9.6°C (air: 17.1°C)
  • September: 9.6°C (air: 15.9°C)
  • October: 9.6°C (air: 13.5°C)
  • November: 9.6°C (air: 10.7°C)
  • December: 9.6°C (air: 8.7°C)

Nearby Dive Sites in Cornwall & Devon

Nearest Dive Centres to CAIRNDHU

Marine Life in Cornwall & Devon

Home to 192 recorded species including 93 reef fish, 18 sharks & rays, 13 whales & dolphins, 11 crabs & lobsters, 11 other, 10 seagrass & algae.

Notable Species

Recommended Packing List for CAIRNDHU

Based on average water temperature of 9.6°C.

  • Drysuit - water at 10°C demands a drysuit with thermal undergarments
  • Hood & Gloves (7mm+) - critical to prevent heat loss
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories