PLM 4 - Cornwall & Devon

PLM 4, a steamship sunk in 1917, lies at 49 meters off the Cornish coast. She's a good deep dive, though currents can be tricky, so we always check the tides before heading out. The wreck itself is in decent shape, broken in places but still very much a ship. You can trace her lines and get a sense of her original form, which is always satisfying on a wreck this old. Expect to see plenty of local colour – conger eels often peek from the darker nooks, and we’ve spotted various crabs scuttling across the plates. It's a dive for those who appreciate history and don't mind the chill of the Atlantic.

Location
Cornwall & Devon, United Kingdom, Mediterranean & Europe
Coordinates
50.129166, -0.883333
Type
wreck
Maximum Depth
49m

Marine Protected Area: Dolphin Head Highly Protected Marine Area

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 PLM 4

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 PLM 4

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

Frequently Asked Questions

What is the typical diving depth range at PLM 4 (Similan Island 4) dive sites?
The PLM 4 dive site, located in Cornwall & Devon, United Kingdom, has a reported depth of 49 meters. While the question mentions Similan Island 4, the provided data specifically details the PLM 4 wreck. Divers should be prepared for a single deep dive to this significant depth.
What kind of marine life and underwater topography can divers expect to see at PLM 4 (Similan Island 4)?
At PLM 4, divers can expect to explore the fascinating underwater topography of a steam ship vessel, sunk on December 27, 1917. This impressive wreck, measuring 77.1m x 13.4m, offers a unique historical diving experience. Details regarding specific marine life are not available in the current data, but wrecks often become artificial reefs attracting various species over time.
How challenging are the dive conditions at PLM 4 (Similan Island 4) for recreational divers?
The dive conditions at PLM 4 are classified as intermediate difficulty. This suggests that divers should possess a good level of experience and comfort with deeper diving and potential wreck exploration, although the wreck itself is classified as non-dangerous. Divers should ensure they are adequately trained and prepared for these conditions.
What is the best time of year to dive at PLM 4 (Similan Island 4) for optimal conditions?
Information regarding the best time of year for optimal diving conditions at PLM 4, including water temperatures or visibility, is not provided in the available data. We recommend consulting local dive operators in Cornwall & Devon or checking our When to Dive section for general guidance on the region.
What scuba diving certifications are required or highly recommended for diving at PLM 4 (Similan Island 4)?
Given the depth of 49 meters and the intermediate difficulty rating for PLM 4, advanced diving certifications are highly recommended. Divers should ideally hold at least an Advanced Open Water certification, and potentially a Deep Diver specialty or even technical diving qualifications, depending on their agency and planned dive profile. Always dive within your certification limits and experience.
Are there strong currents or specific water conditions to be aware of when diving at PLM 4 (Similan Island 4)?
The provided data for PLM 4 does not include specific information about strong currents or other particular water conditions. As conditions can vary, it is always advisable to consult with local dive centers in Cornwall & Devon immediately prior to your dive. They can provide the most up-to-date information on local conditions.