Cornwall, Devon and Dorset have an interesting coast for divers with rocky headlands and bays more evident.  Cornwall in particular is renowned for the wrecks, dive sites and prolific marine life at a variety of depths.  Visibility is very good but does vary. Tidal streams are strong and there are many dangerous reefs. The Scilly Isles are off the coast of Cornwall with great visibility and wrecks.

In Cornwall and the Scilly Isles (28 miles off Lands End), there is lots of good diving and the added attraction is that seals will probably come and play with you.  The Manacles located off the South Cornish coast is very popular with a choice of reefs or wreck diving.  There are sheer-sided pinnacles and walls starting at 5 metres and going down to 50 metres, along with rocks and gullies full of jewel anemones, crustaceans, soft corals, hydroids, anenomes, plus plenty of fish. Download a Guide to Falmouth's Local Marine Life.

Cornwall, too, has it's share of wrecks.  Download a Guide to Falmouth's Wrecks.

In Dorset there are numerous wrecks from submarines to fighting ships, cargo ships to passenger ships.  Lyme Bay was considered the only safe anchorage to shelter during storms.  Even so, many vessels still came to grief and Lyme Bay itself is now so littered with wrecks that it is often referred to as 'The Bay of a Thousand Wrecks'.  See more details here.

Several Dorset wrecks have been adopted by sport divers under the 'Adopt a Wreck' scheme organised by the Nautical Archaeological Society. This encourages recreational divers to take a serious interest in particular wrecks. 

• In the Bristol Channel, the Isle of Lundy (a marine reserve in the Bristol Channel) has superb diving with rocky walls teeming with marine life.  Diving tends to be retricted to May-September and the dive boats leave from Bideford and Ilfracombe.  Around the island there are over 130 wrecks, the most famous being the 14,000 tonne battleship, HMS Montague, which ran aground in 1906. A lot of the wreck was salvaged, but there is still a lot to see.  The depth is 7-12 metres. 
• Gannet's Rock and Knoll Pins are other notable dives. 
• In early summer, basking sharks are attracted by the plankton bloom.

• HMS Scylla - a decommissioned Leander class frigate of the Royal Navy which sank in 2004. She is the first artificial reef in the UK. The gun mounts, depth charge racks and missile launchers are still in place and it is a fascinating wreck to dive. There are lots of swimthroughs which were cut into the ship before she sunk and others which were created by the charges which punched holes in the hull. These tend to be a bit ragged, so caution is needed. The swim-throughs can lead down corridors in the ship, but in general there is always an exit near by.
• The James Egan Layne - one of the 2,700 Liberty ships built by the US during WW2, she was on her maiden voyage when struck by a torpedo from the U-1195. 
• The Mohegan - a large 428 foot four masted luxury liner, which sank with the loss of 192 lives.  Most of the victims are buried in St Keverne Church in a mass grave which is marked by a simple cross.  On the dive you can see lots of fan coral, dead men's fingers, jewel anemones and a vast array of fish life such as pollack, pouting, cod, ling, wrasse, bass etc. 
• The City of Ghent, a small coaster, sunk in 1956.  
• The area around the Lizard Peninsula has become one of the foremost sites in the UK for observing basking sharks attracted by abundant plankton blooms, especially in early summer.

Dorset:

• Lyme Bay - The Bay of a Thousand Wrecks. 

• General visibility is better than for other regions in England, although it is variable.  
• Eighteen sites off the Dorset Coast receive some form of protection. Four have legal protection, which restricts activities on the site, whilst the other fourteen have been adopted by amateur groups under a scheme run by the Nautical Archaeological Society.
• For wrecks designated as Controlled Sites under the Protection of Military Remains Act 1986, diving on these sites is effectively forbidden. Full details of the legislation can be found on the Receiver of Wreck's website.