What is an isthmus? The isthmus definition is fairly simple. An isthmus is a long, thin strip of land that connects two land masses. It has water on both sides. Some isthmuses are tombolos. A tombolo is a coastal sedimentary deposit of sand, gravel or silt that connects an island to the mainland. There are many isthmuses in the world, as evidenced by the following list of worldwide isthmus examples.
- The Isthmus of Panama is famous because the Panama Canal was built through it. It links Costa Rica and South America. It's located between the Caribbean Sea and the Pacific Ocean.
- The Isthmus of Rivas is located in Nicaragua. It is bounded by the Pacific Ocean on one side and Lake Nicaragua on the other.
- The Isthmus of Tehuantepec connects Mexico with the Yucatan Peninsula and Central Mexico. It is bordered by the Gulf of Mexico and the Pacific Ocean.
- In Argentina, the Istmo Carlos Ameghino links Peninsula Buckets and the Province of the Chubut. It is bordered by Gulfo Nuevo (New Gulf) and Golfo San Jose.
- In Argentina, the Quetrihué Isthmus is in Nahuel Huapi Lake, which is a popular tourist area in the northern portion of Patagonia.
- In the southern Atlantic Ocean, the Isthmus of East Falkland unites East Falkland and Lafonia to comprise the largest of the Falkland Islands.
- In Chile, the Ofqui Isthmus connects the Chilean mainland with the Taitao Peninsula, parts of which are located within Chile's Laguna San Rafael National Park.
- Also in Chile, the Isthmus of Muñoz Gamero unites the Muñoz Gamero Peninsula with the Patagonia mainland.
- The Isthmus of Brunswick Peninsula is also in Chile. It is located between Otway Sound and the Strait of Magellan.
- The Isthmus of Médanos is in Venezuela. It links the Paraguana Peninsula to Venezuela's mainland.
There are many isthmuses north of the ones listed above. The countries that comprise North America are home to a number of isthmuses.
- The Isthmus of Avalon unites the Avalon Peninsula to the mainland of Newfoundland.
- The Isthmus of Chignecto links Nova Scotia and New Brunswick to North America, specifically Canada.
- The Isthmus of the Sechelt Peninsula separates the Sechelt Inlet from the Strait of Georgia.
- The Isthmus of Saint Pierre and Miquelon connects Langlade Island with the island of Miquelon.
- The Isthmus of Summerside unites the western portion of Prince Edward Island with the rest of the island.
- The Madison Isthmus is in Madison, Wisconsin. It connects Lake Mendota and Lake Monona.
- Seattle, Washington is located on an isthmus that is between the Puget Sound and Lake Washington.
- In Maui, Hawaii, Central Maui is an isthmus that connects two volcanic masses. Central Maui links Haleakala to West Maui.
- Coronado, California is located on a peninsula that is connected to the mainland by an isthmus called the Silver Strand.
- The Catalina Isthmus is between the small western region of Santa Catalina Island, California and its larger eastern area.
- In Massachusetts, the Isthmus of Nahant connects two small islands, Nahant and little Nahant, to the state's mainland.
- The Isthmus of Olympia, Washington links East Olympia to West Olympia. It also separates Budd Inlet (part of Puget Sound) and Capitol Lake.
The eastern part of the world is also home to a number of Isthmus examples. There are many examples of isthmuses throughout Africa and Asia, as well as Russia.
- The Isthmus of Mansheya connects Egypt's island of Pharos to the city of Alexandria on the country's mainland.
- The Isthmus of Suez in Egypt joins Africa and Asia and is the location of the Suez Canal.
- The Isthmus of Kra links the Malay Peninsula with the mainland of Asia.
- The Isthmus of Kushimoto in Japan joins Cape Shiono-Misaki and Honshū.
- In the Quezon Province of Luzon in the Phillippines, the Tayabas Isthmus unites the mainland of Luzon with the Bicol Peninsula.
- Adam's Bridge, also known as Rama's Bridge, is an isthmus that connects Sri Lanka and India.
- In Russia, the Karelian Isthmus is found between Lake Ladoga and the Gulf of Finland (the Baltic Sea).
- In the northern portion of Russia, Olonets Isthmus is located between Lake Ladoga and Lake Onega.
- Also in northern Russia, Onega Isthmus lies between Lake Onega and the White Sea.
Many isthmus examples can be found throughout both Eastern Europe and Western Europe.
- The Isthmus of Perekop connects the Peninsula of Crimea and the Ukraine Mainland.
- The Isthmus of Westfjords peninsula unites its namesake peninsula with the mainland of Iceland.
- The Isthmus of Corinth joins the Peloponnese Peninsula with Greece.
- The Isthmus of Potidea links the Kassandra Peninsula with Greece.
- The Isthmus of Gibraltar joins Gibraltar and Spain.
- The La Coupée isthmus unites Great Sark and Little Sark.
- In the Shetland Islands, the Mavis Grind isthmus connects Northmavine and the rest of the Shetland Mainland. It lies between the Atlantic Ocean and the North Sea.
The land down under is also a place where isthmuses can be found. There are isthmuses in both Australia and New Zealand.
- The Auckland Isthmus links the Northland Peninsula with the rest of New Zealand's North Island.
- The Rongotai isthmus in Wellington, New Zealand is between the Miramar Peninsula and the two suburbs of Kilbirnie and Lyall Bay.
- The Neck in Bruny Island, Tasmania joins North and South Bruny.
- Eaglehawk Neck connects mainland Tasmania with the Tasman Peninsula.
- The Taillefer Isthmus is located in Western Australia. It connects the western coast of Australia's Gascoyne region to the Peron Peninsula.
- East Bay Neck is located in Tasmania. It connects the Forestier Peninsula to Tasmania's mainland.
Isthmuses are important geographic features, examples of which can be seen throughout the world. Although some are made of land and others of more granular particles, such as sand, they all link two land masses together and have water on both sides. Now that you're familiar with isthmus examples, continue building your knowledge of geography by learning some key examples of geography terms.