Longest chalk reef
A 20-mile chalk reef
United Kingdom Norfolk,England
The world’s longest chalk reef, consisting of a series of enormous arches and deep chasms, stretches for over 20 miles along the coast of Norfolk, England. Approximately 300 million years old, it is home to numerous species of fish, sea slugs, sponges, and other marine life, and is one-and-a-half times longer than the previous record holder, the Thanet Coast chalk reefs of Kent. It was discovered by diver Rob Spray and a team of 20 volunteer conservationists in early 2010.