Tied island

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View from the Isle of Portland looking towards the mainland of Great Britain. Chesil Beach on the left connects the tied island to the mainland Uk dor portharbour.JPG
View from the Isle of Portland looking towards the mainland of Great Britain. Chesil Beach on the left connects the tied island to the mainland
St Ninian's Isle, a tied island during all but the very highest tides Tombolo St Ninians 5940.JPG
St Ninian's Isle, a tied island during all but the very highest tides

Tied islands, or land-tied islands as they are often known, are landforms consisting of an island that is connected to land only by a tombolo: a spit of beach materials connected to land at both ends. St Ninian's Isle, in the Shetland Islands off the north coast of Scotland, is an example of this; it was once an island but is now linked to the Mainland. Other examples include: Maury Island, Washington in the Puget Sound, Coronado, California and Nahant, Massachusetts in the U.S.; Barrenjoey, New South Wales in Australia; Wedge Island in Western Australia; Cheung Chau in Hong Kong and Davaar Island, Campbeltown, Scotland.

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The Isle of Portland is also described as a tied island, although geographers now believe that Chesil Beach (which connects the island to the mainland) is a barrier beach that has moved eastwards, rather than a tombolo, which would have been formed by the effect of the island on waves.

Paniquian Island (also known as Isla Boquete) is a tied island in Puerto Galera, a popular tourist destination in the Philippines. The island is connected to the main island of Mindoro by a small tombolo that is only submerged a few times per year.

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Islands of the Clyde Scottish island group

The Islands of the Firth of Clyde are the fifth largest of the major Scottish island groups after the Inner and Outer Hebrides, Orkney and Shetland. They are situated in the Firth of Clyde between Ayrshire and Argyll and Bute. There are about forty islands and skerries. Only four are inhabited, and only nine are larger than 40 hectares. The largest and most populous are Arran and Bute. They are served by dedicated ferry routes, as are Great Cumbrae and Holy Island. Unlike the isles in the four larger Scottish archipelagos, none of the isles in this group are connected to one another or to the mainland by bridges.

Islet Very small island

An islet is a very small island. Most definitions are not precise, but some suggest that an islet has little or no vegetation, and cannot support human habitation. They may be made of rock, sand, and/or coral, may be permanent or tidal, and may exist in the sea, rivers, or any other body of water.

Isle of Portland Human settlement in England

The Isle of Portland is a tied island, 6 kilometres (4 mi) long by 2.7 kilometres (1.7 mi) wide, in the English Channel. Portland is 8 kilometres (5 mi) south of the resort of Weymouth, forming the southernmost point of the county of Dorset, England. A barrier beach called Chesil Beach joins it to the mainland. The A354 road passes down the Portland end of the beach and then over the Fleet Lagoon by bridge to the mainland. The population of Portland is 12,797.

Jurassic Coast World Heritage Site on the coast of southern England

The Jurassic Coast is a World Heritage Site on the English Channel coast of southern England. It stretches from Exmouth in East Devon to Studland Bay in Dorset, a distance of about 96 miles (154 km), and was inscribed on the World Heritage List in mid-December 2001.

Tombolo Deposition landform in which an island is connected to the mainland by a sandy isthmus

A tombolo is a sandy isthmus. A tombolo, from the Italian tombolo, meaning 'pillow' or 'cushion', and sometimes translated as ayre, is a deposition landform by which an island becomes attached to the mainland by a narrow piece of land such as a spit or bar. Once attached, the island is then known as a tied island.

Chesil Beach Shingle beach in southern England

Chesil Beach in Dorset, England is one of three major shingle beach structures in Britain. Its name is derived from the Old English ceosel or cisel, meaning "gravel" or "shingle". It runs for a length of 29 kilometres (18 mi) from West Bay to the Isle of Portland and in places is up to 15 metres (50 ft) high 200 metres (660 ft) wide. Behind the beach is the Fleet, a shallow tidal lagoon. Both are part of the Jurassic Coast and a UNESCO World Heritage Site, and together form an SSSI and Ramsar Site.

Shoal Natural submerged sandbank that rises from a body of water to near the surface

In oceanography, geomorphology, and earth sciences, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material, and rises from the bed of a body of water to near the surface. Often it refers to those submerged ridges, banks, or bars that rise near enough to the surface of a body of water as to constitute a danger to navigation. Shoals are also known as sandbanks, sandbars, or gravelbars. Two or more shoals that are either separated by shared troughs or interconnected by past or present sedimentary and hydrographic processes are referred to as a shoal complex.

Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.

Spit (landform) Coastal bar or beach landform deposited by longshore drift

A spit or sandspit is a deposition bar or beach landform off coasts or lake shores. It develops in places where re-entrance occurs, such as at a cove's headlands, by the process of longshore drift by longshore currents. The drift occurs due to waves meeting the beach at an oblique angle, moving sediment down the beach in a zigzag pattern. This is complemented by longshore currents, which further transport sediment through the water alongside the beach. These currents are caused by the same waves that cause the drift.

Mainland, Orkney Main island of the Orkney Islands, Scotland

The Mainland, also known as Hrossey and Pomona, is the main island of Orkney, Scotland. Both of Orkney's burghs, Kirkwall and Stromness, lie on the island, which is also the heart of Orkney's ferry and air connections.

Skerry A rocky island smaller than an islet

A skerry is a small rocky island, or islet, usually too small for human habitation. It may simply be a rocky reef. A skerry can also be called a low sea stack.

St Ninians Isle Island in Shetland, United Kingdom

St Ninian's Isle is a small tied island connected by the largest tombolo in the UK to the south-western coast of the Mainland, Shetland, in Scotland. It is part of the civil parish of Dunrossness on the South Mainland. The tombolo, known locally as an ayre from the Old Norse for "gravel bank", is 500 metres long. During the summer the tombolo is above sea level and accessible to walkers. During winter, stronger wave action removes sand from the beach so that it is usually covered at high tide, and occasionally throughout the tidal cycle, until the sand is returned the following spring. Depending on the definition used, St. Ninian's is thus either an island, or a peninsula; it has an area of about 72 hectares.

Storm beach

A storm beach is a beach affected by particularly fierce waves, usually with a very long fetch. The resultant landform is often a very steep beach composed of rounded cobbles, shingle and occasionally sand. The stones usually have an obvious grading of pebbles, from large to small, with the larger diameter stones typically arrayed at the highest beach elevations. It may also contain many small parts of shipwrecked boats.

South Walls

South Walls, often referred to as Walls is an inhabited island adjacent to Hoy in Orkney, Scotland. The name is a corruption of "Sooth Was", which means the "southern voes" - as with Kirkwall, it was assumed that it was a mispronunciation of "walls".

Ayre (landform) Shingle beaches in Orkney and Shetland

An ayre is the name used for shingle beaches in Orkney, Shetland and the Isle of Man. The word is derived from the Old Norse eyrr, meaning a shingle beach or gravelly place, and may be applied to ordinary beaches, cliff-foot beaches such as the Lang Ayre in Northmavine, Shetland, spits, bars or tombolos, but only if formed of shingle. More than 130 such shingle beaches are named on Ordnance Survey maps of Shetland, but far fewer in Orkney, where most beaches are formed of sand. The word in its Old Norse form is common in Iceland, and it also occurs in a few place names in the north and west of the Scottish mainland which had a strong Norse influence, such as Eriboll and in the names of several shingle banks - Salt Ayre, Green Ayre, Stake Ayre, Rabbit Ayre and Whinny Ayre - in the tidal reach of the River Lune at Lancaster.

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