An isthmus ( / ˈ ɪ s m ə s , ˈ ɪ s θ m ə s / ; pl. : isthmuses or isthmi ) is a narrow piece of land connecting two larger areas across an expanse of water by which they are otherwise separated. A tombolo is an isthmus that consists of a spit or bar , and a strait is the sea counterpart of an isthmus, a narrow stretch of sea between two landmasses that connects two larger bodies of water.
15-597: Eaglehawk Neck , officially Teralina / Eaglehawk Neck , is a narrow isthmus that connects the Tasman Peninsula with the Forestier Peninsula and hence to the rest of Tasmania , Australia. It is about 26 kilometres (16 mi) north-east of the town of Nubeena in the local government area of Tasman in the South-east region of Tasmania. At the 2016 census , the locality had a population of 385. The isthmus
30-505: A World Heritage Site that comprises eleven remnant penal sites originally built within the British Empire during the 18th and 19th centuries on fertile Australian coastal strips. Collectively, these sites, including Port Arthur, now represent, "...the best surviving examples of large-scale penal transportation and the colonial expansion of European powers through the presence and labour of convicts". The first Eagle Hawk Neck post office
45-407: A particularly advantageous shortcut for marine transport. For example: Strait A strait is a water body connecting two seas or two water basins. While the landform generally constricts the flow, the surface water still flows, for the most part, at the same elevation on both sides and through the strait in both directions. In some straits there may be a dominant directional current through
60-453: Is a holiday destination. On the eastern side, a beach that stretches around Pirates' Bay is a popular surfing area. In summer the population rises as people return to their holiday homes. Eaglehawk Neck was gazetted as a locality in 1967. It was dual named in March 2021 to include its original name, Teralina. As Eaglehawk Neck forms a natural thin gateway between the peninsulas, it was used by
75-675: Is a land connection between two bigger landmasses, while a peninsula is rather a land protrusion that is connected to a bigger landmass on one side only and surrounded by water on all other sides. Technically, an isthmus can have canals running from coast to coast (e.g. the Panama Canal ), and thus resemble two peninsulas; however, canals are artificial features distinguished from straits . The world's major isthmuses include: Of historic importance were: The cities of Auckland , Madison , Manila , and Seattle are located on isthmuses. Canals are often built across isthmuses, where they may be
90-476: Is around 400 metres (1,300 ft) long and less than 30 metres (98 ft) wide at its narrowest point. The location features rugged terrain and several unusual geological formations including the Tessellated Pavement . Clyde Island, at the northern entry to Pirates Bay, is accessible for crossings at low tide and is the site of two graves, and a rumbling blow hole that cleaves the island. Eaglehawk Neck
105-556: Is sometimes differentiated with varying senses. In Scotland, firth or Kyle are also sometimes used as synonyms for strait. Many straits are economically important. Straits can be important shipping routes and wars have been fought for control of them. Numerous artificial channels, called canals , have been constructed to connect two oceans or seas over land, such as the Suez Canal . Although rivers and canals often provide passage between two large lakes, and these seem to suit
120-549: The British as a place to stop convicts attempting to escape from Port Arthur and other penal institutions on the Tasman Peninsula. A system was developed where a line of dogs were chained to posts across the "Neck" to warn of any convicts attempting to escape. The Dog Line was first implemented in 1831 and was used until the closure of Port Arthur in the 1870s. Thomas J. Lempriere, a commissary officer at Port Arthur, declared
135-629: The Eaglehawk Neck as "impassable". Despite this, many attempts were made by convicts to escape from the Tasman Peninsula via Eaglehawk Neck, including Martin Cash and William Bannon . The area was heavily patrolled by soldiers, and the guards' quarters still remains as a museum. The isthmus now provides road access via the Arthur Highway to Port Arthur, part of the Australian Convict Sites ,
150-511: The centre and runs south-east until it ends at Tasman Arch. Isthmus Isthmus and land bridge are related terms, with isthmus having a broader meaning. A land bridge is an isthmus connecting Earth's major land masses. The term land bridge is usually used in biogeology to describe land connections that used to exist between continents at various times and were important for the migration of people and various species of animals and plants, e.g. Beringia and Doggerland . An isthmus
165-577: The converse of isthmuses . That is, while a strait lies between two land masses and connects two large areas of ocean, an isthmus lies between two areas of ocean and connects two large land masses. Some straits have the potential to generate significant tidal power using tidal stream turbines . Tides are more predictable than wave power or wind power . The Pentland Firth (a strait) may be capable of generating 10 GW . Cook Strait in New Zealand may be capable of generating 5.6 GW even though
SECTION 10
#1732859512060180-475: The formal definition of strait, they are not usually referred to as such. Rivers and often canals, generally have a directional flow tied to changes in elevation, whereas straits often are free flowing in either direction or switch direction, maintaining the same elevation. The term strait is typically reserved for much larger, wider features of the marine environment. There are exceptions, with straits being called canals; Pearse Canal , for example. Straits are
195-531: The strait. Most commonly, it is a narrowing channel that lies between two land masses . Some straits are not navigable, for example because they are either too narrow or too shallow, or because of an unnavigable reef or archipelago . Straits are also known to be loci for sediment accumulation. Usually, sand-size deposits occur on both the two opposite strait exits, forming subaqueous fans or deltas . The terms channel , pass , or passage can be synonymous and used interchangeably with strait , although each
210-477: The total energy available in the flow is 15 GW. Straits used for international navigation through the territorial sea between one part of the high seas or an exclusive economic zone and another part of the high seas or an exclusive economic zone are subject to the legal regime of transit passage ( Strait of Gibraltar , Dover Strait , Strait of Hormuz ). The regime of innocent passage applies in straits used for international navigation (1) that connect
225-452: Was open from 1875 until 1877. A post office opened on 11 January 1895 and closed in 1974. The shores of Norfolk Bay and Eaglehawk Neck form the western boundary, while the Tasman Sea forms the eastern. The A9 route ( Arthur Highway ) enters from the north and runs through to the south-west, where it exits. Route C338 (Blowhole Road / Tasmans Arch Road) starts at an intersection with A9 in
#59940