CALEDONIA (BCK 375) - Scapa Flow, Orkney

The Caledonia, a fishing trawler that burned and sank in 1923, sits upright and largely intact at 57 metres. We think it’s a brilliant dive for those comfortable with deeper wrecks in colder water. You descend onto the stern, where the propeller still offers a stark photo opportunity against the low light of Scapa Flow. The wheelhouse is gone, but the hull itself is a haven for life. We’ve often found substantial ling and conger eels tucked into the hold, alongside dense schools of saithe swirling around the mast. The visibility here can be surprisingly good on a calm day, sometimes pushing 10-15 metres, which really lets you appreciate the scale of the trawler. Exploring the deck allows you to trace the fire’s path, imagining the crew’s final moments. Keep an eye out for nudibranchs on the superstructure – we’ve seen some unusual varieties. It’s a site that rewards multiple visits; each dive reveals another detail, another resident.

Location
Scapa Flow, Orkney, United Kingdom, Mediterranean & Europe
Coordinates
57.562220, -3.955563
Type
wreck
Maximum Depth
57m

Wreck History - CALEDONIA (BCK 375)

Year Sunk
1923
Vessel Type
fishing vessel
Cause
fire

The Caledonia (BCK 375) was a motor fishing vessel registered in the Scottish port of Buckie. Owned by James & Alexander Smith of Portessie, she was a workhorse of the North Sea fishing fleet. On August 27, 1923-coincidentally the very same day the much larger HMS Caledonia sank nearby-disaster struck the fishing boat. A fire broke out on board, and despite the crew's efforts, it quickly raged out of control. The vessel was consumed by flames and sank, though thankfully her crew of four was recovered safely.

Resting at a depth of 57 metres, the Caledonia is a deep, challenging dive reserved for experienced technical and trimix divers. Lying in the dark, cold waters of Scapa Flow, the wreck is often subject to strong currents. Those qualified to make the descent will find the remains of a classic early 20th-century fishing boat. Depending on how she landed, divers might identify her engine, winches, and the general outline of her hull, now heavily colonized by anemones and other deep-water marine life.

Marine Protected Area: Whiteness Head

Best Time to Dive in Scapa Flow, Orkney

The warmest water temperatures in Scapa Flow, Orkney occur in January, averaging 8.4°C. The coolest conditions are in December at 8.4°C.

Monthly Water Temperatures

  • January: 8.4°C (air: 5.5°C)
  • February: 8.4°C (air: 5.3°C)
  • March: 8.4°C (air: 5.9°C)
  • April: 8.4°C (air: 6.8°C)
  • May: 8.4°C (air: 9.7°C)
  • June: 8.4°C (air: 12.4°C)
  • July: 8.4°C (air: 13.2°C)
  • August: 8.4°C (air: 13.7°C)
  • September: 8.4°C (air: 12.7°C)
  • October: 8.4°C (air: 10.2°C)
  • November: 8.4°C (air: 8.0°C)
  • December: 8.4°C (air: 5.8°C)

Nearby Dive Sites in Scapa Flow, Orkney

Nearest Dive Centres to CALEDONIA (BCK 375)

Marine Life in Scapa Flow, Orkney

Home to 155 recorded species including 63 reef fish, 17 whales & dolphins, 12 sharks & rays, 11 crabs & lobsters, 11 other, 10 seagrass & algae.

Notable Species

Recommended Packing List for CALEDONIA (BCK 375)

Based on average water temperature of 8.4°C.

  • Drysuit - water at 8°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