HMS M1

Best months: Jul–Sep

Protected Area

Start Point to Plymouth Sound and Eddystone

Why dive here

With 176+ marine species recorded in the area - including blue sharks, dolphins, dwarf minke whales, humpback whales and ocean sunfish (mola mola) - HMS M1 offers some of Cornwall & Devon's richest wreck diving. Water ranges 10-18°C, warmest July, August, September.

Best timeJul–Sep

WetsuitA 5mm wetsuit

Marine lifeBlue Sharks, Dolphins, Dwarf Minke Whales, Humpback Whales and Ocean Sunfish (Mola Mola) · 176+ species recorded

Water10-18°C · warmest July, August, September

CharacterWreck dive

StandoutExceptional marine biodiversity

The HMS M1 wreck is a proper piece of history down there, and one we always enjoy visiting. We love the sheer scale of the M1, a massive submarine that went down in 1925, taking 69 men with her. Dropping onto her deck, it feels like you're stepping back in time. You can spend a good chunk of a dive just exploring her bow, seeing where the massive torpedo tubes once sat. The conning tower is usually a highlight, often draped in dead man's fingers and home to some seriously big wrasse. We’ve spotted common eagle rays cruising past the stern more than once, a truly special sight in these waters. Visibility can be a bit of a lottery, as it often is off the UK coast, but when it's good, it’s a truly impressive dive. We'd suggest aiming for slack water, or you’ll be working for it – the currents here can be a bit lively. It’s a dive for those who appreciate maritime history and don't mind the chill of the Atlantic.