Weymouth & Portland

Almost everything offshore is a hardboat day out of Portland Marina and Portland Harbour, one of the largest man-made harbours in the world. Skin Deep Diving works an 11 m catamaran built for divers; Scimitar Diving is coded to carry twelve divers up to sixty miles offshore, so wrecks like the Aeolian Sky, twelve miles out, are a straightforward run. Several of the named wrecks have to be dived on slack water, so the day is set by the tide table. When the forecast closes the open sea, what is left is the wrecks inside the breakwaters.

The steel is the reason to come. Three submarines carry the area: the M2 upright with her keel at 30 m, UB-74 at about 34 m, and P-555 at 39 m, still largely whole. The merchant losses of 1939 sit a little shallower, the Elena R at about 27 m and the Alex van Opstal on a seabed at 30 m. Inside the breakwaters are HMS Hood, scuttled across the southern entrance in 1914 and known locally as Old Hole in the Wall, along with barges, a WWII landing craft, a Sea Vixen aircraft and the 1850s liner Himalaya. Restricted water exchange inside the harbour lifts temperatures enough that several species live there beyond the usual northern limit of their range.

The area suits divers building UK wreck experience rather than divers chasing a single headline hull. Chesil Cove takes trainees and needs no special skills; the harbour wrecks are sheltered inside the breakwaters; the submarines are the step up, and P-555 is pitched at divers holding a deep or extended-range qualification, with Iolanthe at 43 m past that again. It is drysuit diving, and drysuit use is its own training, done in a pool and at an inland site first. Portland Bill has a notorious tidal race and the Shambles sandbank alongside it, so the offshore programme is weather- and tide-led. Divers who want a bigger and deeper fleet in one anchorage should go to Scapa Flow.