Sian Lowland or Oversian basin ( uk, Надсіанська котловина) is a lowland located at the border between

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...

and

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

along the

San River The San ( pl, San; uk, Сян ''Sian''; german: Saan) is a river in southeastern Poland and western Ukraine, a tributary of the river Vistula, with a length of (it is the 6th-longest Polish river) and a basin area of 16,877 km2 (14,42 ...

. Most of the region is located in Poland except for a small portion in southeastern end which is in Ukraine. The lowland is located between

Malopolska Upland Lesser Poland, often known by its Polish name Małopolska ( la, Polonia Minor), is a historical region situated in southern and south-eastern Poland. Its capital and largest city is Kraków. Throughout centuries, Lesser Poland developed a s ...

, Carpathian Foothills,

Opillia Upland Opillia ( uk, Опілля, ) is a geographic region of the Podolian Upland in Lviv Oblast, Ivano-Frankivsk Oblast and Ternopil Oblast in western Ukraine. It is a western region of the Podillia Upland that stretches along the left bank of Dnieste ...

and

Roztochia Roztocze ( uk, Розточчя, ''Roztochia'') is a range of hills in east-central Poland and western Ukraine which rises from the Lublin Upland and extends southeastward through Solska Forest and across the border into Ukrainian Podolia. Low and ...

. To the southeast it extends into Dniester Lowland over the Sian-Dniester Divide. The Sian Lowland is a tectonic depression along the foothills of the

Carpathian Mountains The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe. Roughly long, it is the third-longest European mountain range after the Urals at and the Scandinavian Mountains at . The range stretches ...

filled in by

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ei ...

(up to thick) covered with

glacial A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betw ...

and

alluvial deposit Alluvium (from Latin ''alluvius'', from ''alluere'' 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluv ...

s. It consists of elevated plateaus (the tallest being Tarnohorod) dissected by the valleys of rivers, such as the

Tanew River Tanew is a river in south-east Poland, a tributary of San. It starts in Roztocze hills. Tanew has a length of about 113 km and its catchment area is 2339 km². Its tributaries are: Potok Łosiniecki (R), Jeleń (R), Sopot (R), Szum ...

, the Liubachivka River, the

Shklo River Shklo ( uk, Шкло, pl, Szkło) is an urban-type settlement in Yavoriv Raion, Lviv Oblast, in southwest Ukraine. It belongs to Novoiavorivsk urban hromada, one of the hromadas of Ukraine. Population: . Shklo is situated in the from the reg ...

, and the Vyshnia River.

Loess Loess (, ; from german: Löss ) is a clastic, predominantly silt-sized sediment that is formed by the accumulation of wind-blown dust. Ten percent of Earth's land area is covered by loess or similar deposits. Loess is a periglacial or aeolian ...

can be found in parts of the plateaus, and dunes are situated in some of its sandy reaches. A large proportion of the lowland's forests have been cleared out, although pine forests mixed with firs and birches occur in the region's sandy areas, and fir forests mixed with

hornbeam Hornbeams are hardwood trees in the flowering plant genus ''Carpinus'' in the birch family Betulaceae. The 30–40 species occur across much of the temperate regions of the Northern Hemisphere. Origin of names The common English name ''hornbeam' ...

s and maples grow in its heavier soils. The lowland has a population density of 80 persons/km²; the population is predominantly (75%) rural.

External links

Sian Lowland
at

Encyclopedia of Ukraine The ''Encyclopedia of Ukraine'' ( uk, Енциклопедія українознавства, translit=Entsyklopediia ukrainoznavstva), published from 1984 to 2001, is a fundamental work of Ukrainian Studies. Development The work was creat ...

Plains of Poland Plains of Ukraine East European Plain {{Ukraine-geo-stub