
Salpausselkä (; "Bar Ridge") is an extensive
ridge
A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, wi ...
system left by the
ice age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages, and g ...
in Southern
Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
. It is a large
terminal moraine
A terminal moraine, also called an end moraine, is a type of moraine that forms at the terminal (edge) of a glacier, marking its maximum advance. At this point, debris that has accumulated by plucking and abrasion, has been pushed by the front e ...
formation that formed in front of the
Baltic ice lake during the
Younger Dryas
The Younger Dryas (YD, Greenland Stadial GS-1) was a period in Earth's geologic history that occurred circa 12,900 to 11,700 years Before Present (BP). It is primarily known for the sudden or "abrupt" cooling in the Northern Hemisphere, when the ...
period about 12,250–10,400 years ago.
All together the formation is close to from end to end, and the ridges can be as tall as in some places.
It runs from
Hanko hundreds of kilometers to the east. It traps the extensive
river
A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...
and
lake
A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...
systems of Central
Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
known as
Finnish Lakeland
Finnish Lakeland or the Finnish lake district ( , "Lake Finland", ) is a large landscape region in central eastern Finland.
The hilly, forest-covered landscape of Lakeland Finland's lake plateau is dominated by drumlins and by long sinuous es ...
(, "Lake Finland") and forces the water to flow through few breaches in the ridge.
The
Vuoksi River
The Vuoksi (, historically: "Uzerva"; ; ; ) is a river running through the northernmost part of the Karelian Isthmus from Lake Saimaa in southeastern Finland to Lake Ladoga in northwestern Russia. The river enters Lake Ladoga in three branches ...
flows from lake
Saimaa
Saimaa ( , ; ) is a lake located in the Finnish Lakeland area in southeastern Finland. With a surface area of approximately , it is the largest lake in Finland, and the fourth-largest natural freshwater lake in Europe.
The name Saimaa likely co ...
into
Lake Ladoga
Lake Ladoga is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, in the vicinity of Saint Petersburg.
It is the largest lake located entirely in Europe, the second largest lake in Russia after Lake ...
() in
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
. From there the water subsequently flows through river
Neva
The Neva ( , ; , ) is a river in northwestern Russia flowing from Lake Ladoga through the western part of Leningrad Oblast (historical region of Ingria) to the Neva Bay of the Gulf of Finland. Despite its modest length of , it is the fourth- ...
into the
Gulf of Finland
The Gulf of Finland (; ; ; ) is the easternmost arm of the Baltic Sea. It extends between Finland to the north and Estonia to the south, to Saint Petersburg—the second largest city of Russia—to the east, where the river Neva drains into it. ...
, bypassing the Salpausselkä. The
Kymi River
The Kymi (, ) is a river in Finland. It begins at Lake Päijänne, flows through the provinces of Päijänne Tavastia, Uusimaa and Kymenlaakso, and discharges into the Gulf of Finland. The river passes the towns of Heinola and Kouvola. The town ...
flows from
Päijänne into the Gulf of Finland. An artificial breach from the Lakeland is the
Saimaa Canal, from Saimaa at
Lappeenranta
Lappeenranta (; ) is a city in Finland and the regional capital of South Karelia. It is located in the southeastern interior of the country and in the Finnish Lakeland. The population of Lappeenranta is approximately , while the Lappeenranta sub-r ...
into the
Gulf of Finland
The Gulf of Finland (; ; ; ) is the easternmost arm of the Baltic Sea. It extends between Finland to the north and Estonia to the south, to Saint Petersburg—the second largest city of Russia—to the east, where the river Neva drains into it. ...
at
Vyborg
Vyborg (; , ; , ; , ) is a town and the administrative center of Vyborgsky District in Leningrad Oblast, Russia. It lies on the Karelian Isthmus near the head of Vyborg Bay, northwest of St. Petersburg, east of the Finnish capital H ...
.
Salpausselkä has been used for transportation because of the easy terrain for centuries; later on both railways and highways have been built to follow it. It is also an important source of clean
groundwater
Groundwater is the water present beneath Earth's surface in rock and Pore space in soil, soil pore spaces and in the fractures of stratum, rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit ...
filtering from the lakes on the upper side (north) of the ridge, for the communities built alongside the ridge. The south side of the Salpausselkä has been inhabited for more than 10,000 years.
There are also formations called ''Second and Third Salpausselkä'', which are similar in form but smaller. They are situated north of the main Salpausselkä, and were formed later respectively.
See also
*
Central Swedish ice-edge zone
References
{{DEFAULTSORT:Salpausselka
Glacial deposits of Finland
Landforms of Finland
Ridges of Europe
Moraines of Europe