_Natural wonder of Norfolk: Chalk reef

Dubbed ‘Britain’s Great Barrier Reef’, the Cromer Shoal Chalk Bed, created when dinosaurs ruled the earth, has been found to be the longest in the world – and it’s so close to the shore you could skim a stone out to it.

At over 20 miles long, the 100-million-year-old reef is one-and-a-half times longer than the Thanet Coast chalk reef in Kent, the former record holder. The chalk reef can be seen at low tide at West Runton and other places between Trimingham and Cley-next-the-Sea.

Discovered only in the early 2020s, the reef is just 25ft under the sea’s surface and has now been made a Marine Conservation Zone (MCZ) between Weybourne and Happisburgh by the Department for Environment Food and Rural Affairs. With an area of 315sq km it’s larger than the Broads National Park.

And it's part of the chalk seam that stretches across England and includes the White Cliffs of Dover and the White Horse Hill Carvings in Wiltshire. 

The white chalk deposits of the Norfolk Coast are from the Upper Cretaceous period, 145 to 66 million years ago. They are the result of millions of tiny plankton skeletons called coccoliths that accumulated on the sea floor and created the deep chalk deposits on which most of Norfolk rests today, seen on exposed cliffs and in the chalk streams. 

The reef, with dramatic features such as tunnels, caves, towering arches and deep chasms made during the Ice Age, has one of the most diverse and spectacular arrays of sea life around Britain – the composition of the reef meaning the water is actually quite warm.

The bed of the North Sea is mostly soft sand and mud, so the hard rocky chalk features create a habitat that attracts all kinds of life.

It provides a unique habitat for biodiversity, providing home to hundreds of species of fish, invertebrates and plant life including Norfolk purple sponge, spring squat lobster, leopard spotted goby fish, burrowing piddocks, sea squirts, anemones, starfish, brittlestars, mossy feather weed and fish including shoaling horse mackerel and bass. 

The clean and nutrient-rich waters are responsible for the flavoursome brown Cancer pogurus, the famed eponymous Cromer Crab.

Three species never before recorded on the east coast have been found: the Atlantic ancula sea slug, the blush-red strawberry anemone and leopard spotted goby.

The MCZ means that sea life such as the threatened pink sea fan coral, which grows on the reef, will now be protected, along with hundreds of species including crabs and lobsters that colonise the soft chalk beds. 

So now you know why Norfolk has the tastiest, most succulent crab and lobster you’ll find in the UK – they have a very special habitat to feed on.

The Sheringham Snorkel Trail was established in 2016, after divers Rob Spray and Dawn Watson came across a Victorian-era iron sewerage pipework and decided it would make an ideal snorkel site. There are details on Sheringham seafront.