It was created by the collapse of a limestone cave in a Silurian reef formation.

There are no seaports in the parish due to the harsh Atlantic waves along the coast and the many dangerous reef formations.

The park has many underwater reef formations, with an average depth ranging from 16 to 36 meters, rich in marine life.

They had been scheduled to dive along a series of reef formations at Roger's Wreck Point.

Briggs & Rolfe report that all the Gogo Thylacocephala are found in a reef formation, suggesting a shallow water environment.

This was the last unexploited reef formation on the planet, which could only mean this formation had been the least interesting, from Thu's standpoint.

The northernmost island arising from the ancient reef formation is Elliott Key, in Biscayne National Park.

Just a few kilometers away lies another highly challenging reef formation: Súľovské skaly.

Large offshore reef formations almost completely surround Dieppe Bay Beach, creating the island's safest natural harbour.

The group is just one of a number of reef formations off the northwest coast of Australia and belongs to Western Australia.