A peninsula is a

landform A landform is a land feature on the solid surface of the Earth or other planetary body. They may be natural or may be anthropogenic (caused or influenced by human activity). Landforms together make up a given terrain, and their arrangement ...

that extends from a mainland and is only connected to land on one side. Peninsulas exist on each continent. The largest peninsula in the world is the

Arabian Peninsula The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world. Geographically, the ...

Etymology

The word ''peninsula'' derives , . The word entered English in the 16th century.

Definitions

A peninsula is generally defined as a piece of land surrounded on most sides by water. A peninsula may be bordered by more than one body of water, and the body of water does not have to be an ocean or a sea. A piece of land on a very tight river bend or one between two rivers is sometimes said to form a peninsula, for example in the New Barbadoes Neck in

New Jersey New Jersey is a U.S. state, state located in both the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. Located at the geographic hub of the urban area, heavily urbanized Northeas ...

, United States. A peninsula may be connected to the mainland via an isthmus, for example, in the

Isthmus of Corinth The Isthmus of Corinth ( Greek: Ισθμός της Κορίνθου) is the narrow land bridge which connects the Peloponnese peninsula with the rest of the mainland of Greece, near the city of Corinth. The wide Isthmus was known in the a ...

which connects to the

Peloponnese The Peloponnese ( ), Peloponnesus ( ; , ) or Morea (; ) is a peninsula and geographic region in Southern Greece, and the southernmost region of the Balkans. It is connected to the central part of the country by the Isthmus of Corinth land bridg ...

peninsula.

Formation and types

Peninsulas can be formed from continental drift, glacial

erosion Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, tran ...

, glacial meltwater, glacial deposition,

marine sediment Marine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor. These particles either have their origins in soil and Rock (geology), rocks and have been Sediment transport, ...

, marine transgressions,

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

es, divergent boundaries or river sedimentation. More than one factor may play into the formation of a peninsula. For example, in the case of

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

, continental drift, marine sediment, and marine transgressions were all contributing factors to its shape. Peninsulas can also be man-made. Typically, they are built as protection from ocean or sea waves by building a Breakwater, which sometimes connects back to land. They can also be built to expand areas of a city; for example,

Copenhagen Copenhagen ( ) is the capital and most populous city of Denmark, with a population of 1.4 million in the Urban area of Copenhagen, urban area. The city is situated on the islands of Zealand and Amager, separated from Malmö, Sweden, by the ...

is planning to create a peninsula that houses 35,000 residents by 2070.

Glaciers

In the case of formation from glaciers (for example, the

Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martin in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. ...

Cape Cod Cape Cod is a peninsula extending into the Atlantic Ocean from the southeastern corner of Massachusetts, in the northeastern United States. Its historic, maritime character and ample beaches attract heavy tourism during the summer months. The ...

), peninsulas can be created due to glacial

, meltwater or deposition. If erosion formed the peninsula, softer and harder rocks were present, and since the glacier only erodes softer rock, it formed a basin. This may create peninsulas, and occurred for example in the

Keweenaw Peninsula The Keweenaw Peninsula (, ) is a peninsula of the U.S. state of Michigan. Part of the greater landmass of the Upper Peninsula of Michigan, Upper Peninsula, the Keweenaw Peninsula projects about northeasterly into Lake Superior, forming Keweena ...

. In the case of formation from meltwater, melting glaciers deposit sediment and form

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

s, which act as dams for the meltwater. This may create bodies of water that surround the land, forming peninsulas. If deposition formed the peninsula, the peninsula was composed of

sedimentary rock Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or de ...

, which was created from a large deposit of glacial drift. The hill of drift becomes a peninsula if the hill formed near water but was still connected to the mainland, for example during the formation of Cape Cod about 23,000 years ago.

Others

In the case of formation from volcanoes, when a volcano erupts

magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as ''lava'') is found beneath the surface of the Earth, and evidence of magmatism has also ...

near water, it may form a peninsula (such as the Alaskan Peninsula). Peninsulas formed from volcanoes are especially common when the volcano erupts near shallow water.

Marine sediment Marine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor. These particles either have their origins in soil and Rock (geology), rocks and have been Sediment transport, ...

may form peninsulas by the creation of

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

. A rift peninsula may form as a result of a

divergent boundary In plate tectonics, a divergent boundary or divergent plate boundary (also known as a constructive boundary or an extensional boundary) is a linear feature that exists between two List of tectonic plates, tectonic plates that are moving away fr ...

plate tectonics Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed durin ...

(such as the

), while a

convergent boundary A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a ...

may also form peninsulas (for example,

Gibraltar Gibraltar ( , ) is a British Overseas Territories, British Overseas Territory and British overseas cities, city located at the southern tip of the Iberian Peninsula, on the Bay of Gibraltar, near the exit of the Mediterranean Sea into the A ...

or the

Indian subcontinent The Indian subcontinent is a physiographic region of Asia below the Himalayas which projects into the Indian Ocean between the Bay of Bengal to the east and the Arabian Sea to the west. It is now divided between Bangladesh, India, and Pakista ...

). Peninsulas can also form due to

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to th ...

in rivers. When a river carrying sediment flows into an ocean, the sediment is deposited, forming a delta peninsula. Marine transgressions (changes in sea level) may form peninsulas, but also may affect existing peninsulas. For example, the water level may change, which causes a peninsula to become an island during high water levels. Similarly, wet weather causing higher water levels make peninsulas appear smaller, while dry weather make them appear larger.

Sea level rise The sea level has been rising from the end of the last ice age, which was around 20,000 years ago. Between 1901 and 2018, the average sea level rose by , with an increase of per year since the 1970s. This was faster than the sea level had e ...

from global warming will permanently reduce the size of some peninsulas over time.

Uses

Peninsulas are noted for their use as shelter for humans and

Neanderthal Neanderthals ( ; ''Homo neanderthalensis'' or sometimes ''H. sapiens neanderthalensis'') are an extinction, extinct group of archaic humans who inhabited Europe and Western and Central Asia during the Middle Pleistocene, Middle to Late Plei ...

s. The landform is advantageous because it gives hunting access to both land and sea animals. They can also serve as markers of a nation's borders. In history, Peninsulas have played vital role in trade and commerce because of their access to water through an isthmus. The

Malay Peninsula The Malay Peninsula is located in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area contains Peninsular Malaysia, Southern Tha ...

, located at the convergence of the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

and the China Seas, played an important role in east-west trade.

List of the largest peninsulas in the world

References

Bibliography

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External links

* {{Authority control Landforms