CARMARTHEN - Cornwall & Devon

The *Carmarthen* sits upright, a proper wreck dive at 18 metres. We love how intact she feels, even after a century on the seabed. This isn't just a pile of twisted metal; you can still make out the bow, the stern, and a lot of her midsection, which really gives you a sense of her scale, 115 metres is a big ship. Drop down onto the deck and push through the slight gloom – that’s part of the charm here, a proper British wreck dive feel. Look for the triple-expansion engine, a real highlight, and we always find some good-sized conger eels tucked away in the darker recesses. Visibility can be a bit of a gamble, but when it’s good, the sheer volume of schooling fish, particularly pollack, around the superstructure is impressive. This is a dive for those who appreciate maritime history and don’t mind a bit of a current.

Location
Cornwall & Devon, United Kingdom, Mediterranean & Europe
Coordinates
50.002365, -5.127100
Type
wreck
Maximum Depth
18m

Wreck History - CARMARTHEN

Year Sunk
1917
Vessel Type
cargo ship
Cause
torpedo
Tonnage
4,262 GRT

The SS Carmarthen had a brief but eventful life, born in the midst of the First World War. Launched in 1916 by W. Gray & Co Ltd, the steamship was operated by James Jenkins of Cardiff. With the war raging, merchant vessels like the Carmarthen were the lifelines of Britain, but they were also prime targets for Germany's U-boat fleet. Her service would last just over a year.

On July 26, 1917, while on a passage from Genoa bound for the River Tees with a cargo of iron ore, the Carmarthen was intercepted by the German submarine UC-47. Without warning, a torpedo struck the vessel, sealing her fate. The ship sank quickly, becoming another casualty of the unrestricted submarine warfare that defined the conflict at sea. The loss was a stark reminder of the constant danger faced by civilian sailors in wartime.

Lying at a depth of just 18 meters, the wreck of the Carmarthen is now a superb and highly accessible dive site for all qualified divers. Over a century on the seabed has left the wreck well broken up, with boilers, engine components, and sections of the hull scattered across the seafloor. This structure has created a thriving artificial reef, attracting a huge amount of marine life. Divers can explore the wreckage while spotting wrasse, pollack, and crustaceans that have taken up residence in the remains of this WWI steamship.

Marine Protected Area: Coverack Cove & Dolor Point

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 CARMARTHEN

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 CARMARTHEN

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