Plymouth Sound & HMS Scylla · United Kingdom · Reef
Breakwater Fort
Old diver-training rigs and wreckage scattered around the base of a sea fort
Photo: Lewis Clarke · CC BY-SA 2.0
Breakwater Fort is a circular Victorian stone and iron fort in the middle of Plymouth Sound, once used as a platform for commercial diver training. The seabed around its base is littered with old training structures and dumped wreckage, which surprises many first-time visitors and gives the dive more to explore than the stonework alone.
Also known as Plymouth Breakwater Fort.
Where it is and how deep
50.3344° N, 4.1490° WApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
A gantry on the north side marks where training divers were once lowered in a lift-cage to the seabed, and the abandoned cage is the first piece of wreckage. Continuing clockwise on the 12 m seabed, a decaying structure almost straight out from the gantry is the old underwater habitat Glaucus, lived in for seven days by two divers in September 1965.
Nearby lies an iron cannon recovered from the 1691 wreck of the Coronation and placed here for safe keeping. The bases of the structures have been undercut by the gentle tide that flows past.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Good | Good | Prime | Prime | Prime | Good | Good | Good |
Season follows Plymouth Sound & HMS Scylla: Diving runs all year when the wind allows; July to September brings the warmest water and the blue shark snorkel trips.
Dive videos
The Breakwater Fort - Plymouth - 14/04/2025 · RP Diving on YouTube
Sources
- Breakwater Fort by kayak — Divernet
- Plymouth Sound — Wikipedia
- OpenStreetMap — OpenStreetMap
Photo credits
- A white lighthouse at the end of a long stone breakwater, with a round stone fort behind it in the water by Lewis Clarke, CC BY-SA 2.0, via Wikimedia Commons
More dive sites in Plymouth Sound & HMS Scylla
Walls of jewel anemones with sea fans on the boulders below
A luxury steam yacht scuttled near the Shag Stone for divers
A whole frigate laid down on sand as Europe's first artificial diving reef
A Liberty ship that went down in the Second World War, beside the Scylla
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