MERCIA - Bornholm

We’ve spent a fair bit of time poking around the Baltic’s wrecks, and the *Mercia* truly stands out. She's a steamship, sunk back in '39, taken as prize then scuttled by a warship. You drop down onto her at 30 metres, and she’s remarkably intact for her age and circumstances. We love how the Baltic’s low light creates this eerie, almost reverent atmosphere around her; it’s not the bright Caribbean, but there’s a quiet beauty to it. The main draw here is the sheer scale and the sense of history. You can spend a whole dive exploring her stern, making your way past the prop and rudder, then pushing up towards the midships. Expect to find her hull encrusted with mussels, and we often spot decent-sized cod lurking in her holds. Our favourite part is navigating the internal structure, imagining the life she once held. The visibility can vary, but on a good day, when the light penetrates, she’s really something special. She’s a solid pick for experienced wreck divers who appreciate a good historical narrative over flashy corals. Bring a good torch and take your time.

Location: Bornholm, Denmark, Mediterranean & Europe
Coordinates: 55.798584, 14.843361
Type: wreck
Maximum Depth: 30m

Marine Protected Area: Bornholm: Davids Banke

Best Time to Dive in Bornholm

The warmest water temperatures in Bornholm occur in January, averaging 3.3°C. The coolest conditions are in December at 3.3°C.

Monthly Water Temperatures

January: 3.3°C (air: 3.1°C)
February: 3.3°C (air: 3.2°C)
March: 3.3°C (air: 3.9°C)
April: 3.3°C (air: 6.0°C)
May: 3.3°C (air: 10.9°C)
June: 3.3°C (air: 16.1°C)
July: 3.3°C (air: 17.4°C)
August: 3.3°C (air: 18.0°C)
September: 3.3°C (air: 15.7°C)
October: 3.3°C (air: 11.5°C)
November: 3.3°C (air: 7.1°C)
December: 3.3°C (air: 3.5°C)

Nearest Dive Centres to MERCIA

Marine Life in Bornholm

Home to 67 recorded species including 43 reef fish, 7 clams & mussels, 5 sea snails & nudibranchs, 4 crabs & lobsters, 2 starfish, 2 other.

Notable Species

Protestant (Clupea harengus) - Reef Fish
Atlantic cod (Gadus morhua) - Reef Fish
Fluke (Platichthys flesus) - Reef Fish
whiting (Merlangius merlangus) - Reef Fish
sprat (Sprattus sprattus) - Reef Fish
dab (Limanda limanda) - Reef Fish
Blue mussel (Mytilus edulis) - Clams & Mussels
Pollock (Trachurus trachurus) - Reef Fish
bull rout (Myoxocephalus scorpius) - Reef Fish
Ocean quahog (Arctica islandica) - Clams & Mussels
eel (Anguilla anguilla) - Reef Fish
four-bearded rockling (Enchelyopus cimbrius) - Reef Fish
New Zealand Mudsnail (Potamopyrgus antipodarum) - Sea Snails & Nudibranchs
anchovy (Engraulis encrasicolus) - Reef Fish
Common sea star (Asterias rubens) - Starfish
lumpsucker (Cyclopterus lumpus) - Reef Fish
saithe (Pollachius virens) - Reef Fish
Split (Scomber scombrus) - Reef Fish
Common cockle (Cerastoderma edule) - Clams & Mussels
Haddock (Melanogrammus aeglefinus) - Reef Fish

Recommended Packing List for MERCIA

Based on average water temperature of 3.3°C.

Drysuit - water at 3°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