A coral reef lies close to shore ; the island's capital of Mutsamudu is also its main port.

At the outer edge of the reef shelf, the bottom slopes very steeply into deep water, at some locations dropping to more than 1, 500 feet ( 457 m ) within 0. 6 miles ( 1 km ) of the shore.

File: Atoll forming-Barrier reef. png | As the subsidence continues the fringing reef becomes a larger barrier reef farther from the shore with a bigger and deeper lagoon inside

The western side of the atoll contains many of Aitutaki's important features including a boat passage through the barrier reef allowing for anchorage close to shore at Arutanga.

At its northward extremity, the reef lies fourteen miles ( 21 km ) from the north shore.

File: Atoll forming-Barrier reef. png | As the subsidence continues, the fringing reef becomes a larger barrier reef further from the shore with a bigger and deeper lagoon inside.

Where the level of the underlying earth allows, the corals grow around the coast to form what he called fringing reefs, and can eventually grow out from the shore to become a barrier reef.

It formed the world's largest barrier reef, 300 – 1, 000 m ( 980 – 3, 300 ft ) from shore, stretching for 2, 000 km ( 1, 200 mi ).

* Fringing reef – this type is directly attached to a shore, or borders it with an intervening shallow channel or lagoon.

* Barrier reef – a reef separated from a mainland or island shore by a deep channel or lagoon

* Apron reef – a short reef resembling a fringing reef, but more sloped ; extending out and downward from a point or peninsular shore

" The reef flat may be a protective area bordering a lagoon, or it may be a flat, rocky area between the reef and the shore.

The fringing reef is a fair distance from the shore at the northern end of Welcome Bay, where it starts at the quite prominent ' Bird Rock '.

These fishponds were typically shallow areas of a reef flat surrounded by a low lava rock wall ( loko kuapa ) built out from the shore.

The eastern shore is composed primarily of rugged rocky cliffs and a reef.

Along the southeast coast off Muri Beach are four small coral islets within a few hundred metres of the shore and within the fringing coral reef.

Those on the north and east sides are 2. 1 to 3 m high, and those on the west and south sides 1. 2 m The reef is completely covered by the sea from 3 hours before to 3 hours after high tide.

The larger of the company's two ships, the William, wrecked on the reef at the north end of what is now called Eleuthera Island, with the loss of all provisions.

The Asian rock is probably a reef off the Yum Burnu ( north of Anadolu Feneri ' Lighthouse of Anatolia '), described by Gyllius:

A second smaller right hand reef break known as ' Richards Reef ' is located 250 metres further north along the beach.

However the reef runs roughly twenty miles north and south by ten miles across, enclosing a vast anchorage with an average depth of 80 to.

* South Pass is also on the West reef, north of SAR Pass.

* Little Bustard (, ) and Big Bustard (, ) are the first and second islets respectively north of Kwajalein island on the East reef, and are the only islets between Kwajalein and Ebeye.

By the 1950s, the Marshallese population coming to work at the base at Kwajalein had grown, and the conditions in the makeshift labor camp on Kwajalein islet were such that the U. S. Navy administering the atoll at the time decided to relocate these Islanders to nearby Ebeye, an islet only three islands to the north of Kwajalein and accessible by a short boat ride or walk over the reef at low tide.

Chlorurus microrhinos from the north coast of East Timor ‎ Parrot fish sleeping at coral reef, Red Sea

The commune of Bora-Bora is made up of the island of Bora Bora proper with its surrounding islets emerging from the coral reef, 29. 3 km² ( 11. 3 sq mi ) in total, and of the atoll of Tupai (), located north of Bora Bora.

The commune of Bora-Bora is made up of the island of Bora Bora proper with its surrounding islets emerging from the coral reef, 29. 3 km² ( 11. 3 sq mi ) in total, and of the atoll of Tupai (), located north of Bora Bora.

There was a jetty to the east of the island, but it has been worn away within the last quarter of the twentieth century, and an extensive drying reef to the north west.

It is found in tropical waters, in lagoons and on outer reef slopes, from the Persian Gulf to Western Australia and throughout the Indian Ocean and Pacific Ocean as far as Melanesia and Micronesia, and as far north as Taiwan, southern Japan and the Ryukyu Islands.

The atoll reef is continuous but almost without islets along the north side.

Bikati and Bikatieta islets occupy a corner of the reef at the extreme northwest tip of the atoll, bordering what may be a second small lagoon to the north of the main lagoon.

The Swedish ship Riksens Ständer hit the reef north of Aegna ( Wolf ) island.

Savai ' i has excellent surfing off reef breaks all around the island, with the best waves during summer on the north coast and the south coast in winter.

Close to shore at Mission Beach lies a shallow reef which runs from the mouth of Porter's Creek at the south end of North Mission Beach almost to Clump Point, the rocky point at the north end of Mission Beach.

In contrast, the western side is composed of reef and several distinct islands, notably the inverted V shape of Atafu Island in the north, Alofi, which extends into the lagoon from the western reef, and the L-shaped Fenualoa in the southwest.

The Cribbar, a reef at the north end of the beach, causes waves to break when the swell is high.

The reef measures more than 50 km from north to south, and is 5 km wide, cut by three passes.

Individual islets on the reef include, from north to south, with their respective locations:

Cartier Island Marine Reserve includes the entire sand cay of Cartier Island, the reef surrounding it, the ocean for a radius around the island, and below the seafloor.

The group proceeded to Little Andaman Island, where they spent ten days surfing several spots for the first time, including Jarawa Point near Hut Bay and the long right reef point at the southwest tip of the island, named Kumari Point.

The terrain is low-lying and sandy: a coral island surrounded by a narrow fringing reef with a depressed central area devoid of a lagoon with its highest point being above sea level.

The narrow fringing reef surrounding the island can be a maritime hazard, so there is a day beacon near the old village site.

The territory covers 780, 000 km < sup > 2 </ sup >, extending east and south from the outer edge of the Great Barrier Reef, and including Heralds Beacon Island, Osprey Reef, the Willis Group, and fifteen other reef / island groups.

A well-developed coral reef that encircles much of the island ensures protection for ships and a habitat for fish.

The shallow reef shelf surrounding the island on the ocean side offers no ocean-side anchorage.

The terrain is low-lying and sandy: a coral island surrounded by a narrow fringing reef with a slightly raised central area.

An atoll is an island formed from a coral reef that has grown on an eroded and submerged volcanic island.

The reef rises to the surface of the water and forms a new island.

The low-lying coral island has long been noted as hard to sight from small ships and is surrounded by a narrow fringing reef.

It was the easy access to fresh water on the island and the rich food source represented by the ocean life sheltered by the reef that made it feasible for the Amerindians to settle this area around 600 BC.

These depths and times are typical of experienced sport divers leisurely exploring a coral reef using 200 bar aluminum cylinders rented from a commercial sport diving operation in most tropical island or coastal resorts.

Oceania, island group of nine islands comprising three reef islands and six true atolls in the South Pacific Ocean, about one-half of the way from Hawaii to Australia.

Accepted as basically correct, his explanation involved considering that several tropical island types — from high volcanic island, through barrier reef island, to atoll — represented a sequence of gradual subsidence of what started as an oceanic volcano.

He reasoned that a fringing coral reef surrounding a volcanic island in the tropical sea will grow upwards as the island subsides ( sinks ), becoming an " almost atoll ", or barrier reef island, as typified by an island such as Aitutaki in the Cook Islands, Bora Bora and others in the Society Islands.