continent lisitsa river
___MASK3___ is a continent that comprises the westernmost part of Eurasia . ___MASK3___ is bordered by the Arctic Ocean to the north , the Atlantic Ocean to the west , and the Mediterranean Sea to the south . To the east and southeast , ___MASK3___ is generally considered as separated from ___MASK45___ by the watershed divides of the Ural and Caucasus Mountains , the Ural River , the Caspian and Black Seas , and the waterways of the Turkish Straits . Yet the non - oceanic borders of ___MASK3___  a concept dating back to classical antiquity  are arbitrary . The primarily physiographic term " continent " as applied to ___MASK3___ also incorporates cultural and political elements whose discontinuities are not always reflected by the continent ' s current overland boundaries . Tomsk Oblast (" Tomskaya oblast ") is a federal subject of Russia ( an oblast ). It lies in the southeastern West Siberian Plain , in the southwest of the Siberian Federal District . Its administrative center is the city of Tomsk . Population : 1 , 047 , 394 ( 2010 Census ). Siberia is an extensive geographical region , and by the broadest definition is also known as North ___MASK45___ . Siberia has historically been a part of Russia since the 17th century . The Lisitsa River , also known as Bolshaya Lisitsa River ( Russian :  ,   ) , is a river in Tomsk Oblast in Russia , a right tributary of the Ket River ( Ob basin ) . The river is 414 kilometres ( 257 mi ) long , and its basin covers 7 , 980 square kilometres ( 3 , 080 sq mi ) . The Lisitsa River flows over the West Siberian Plain . Its biggest tributary is the Raiga River . This article includes content derived from the Great Soviet Encyclopedia , 1969 -- 1978 , which is partially in the public domain . ___MASK22___ is the combined continental landmass of ___MASK3___ and ___MASK45___ . The term is a portmanteau of its constituent continents . Located primarily in the Northern and Eastern Hemispheres , it is bordered by the Atlantic Ocean to the west , the Pacific Ocean to the east , the Arctic Ocean to the north , and by Africa , the Mediterranean Sea , and the Indian Ocean to the south . The division between ___MASK3___ and ___MASK45___ as two different continents is a historical and cultural construct , with no clear physical separation between them ; thus , in some parts of the world , ___MASK22___ is recognized as the largest of five or six continents . In geology , ___MASK22___ is often considered as a single rigid megablock . However , the rigidity of ___MASK22___ is debated based on the paleomagnet data . Chelyabinsk is a city and the administrative center of Chelyabinsk Oblast , Russia , located in the northeast of the oblast , south of Yekaterinburg , just to the east of the Ural Mountains , on the Miass River , on the border of ___MASK3___ and ___MASK45___ . Population : Russia is not proportionately populated between the smaller western portion ( almost 25 %) of the country that is considered part of ___MASK3___ , and the larger eastern portion ( more than 75 %) that is part of ___MASK45___ . European Russia contains about 77 % of the country ' s population ( 110 , 000 , 000 people out of about 144 , 000 , 000 ) in an area comprising almost 4 million km ( 1 . 54 million mi ); an average of 27 . 5 persons per km ( 70 per mi ). This territory makes up 38 % of ___MASK3___ . Its eastern border is defined by the Ural Mountains and in the south , it is defined by the border with Kazakhstan . This area includes Moscow and Saint Petersburg , the two largest cities in Russia . Russia ( from the  Rus '), also officially known as the Russian Federation , is a country in ___MASK22___ . At , Russia is the largest country in the world by surface area , covering more than one - eighth of the Earth ' s inhabited land area , and the ninth most populous , with over 140 million people at the end of March 2016 . The European western part of the country is much more populated and urbanised than the eastern , about 77 % of the population live in European Russia . Russia ' s capital Moscow is one of the largest cities in the world , other major urban centers include Saint Petersburg , Novosibirsk , Yekaterinburg , Nizhny Novgorod and Samara . Yekaterinburg , alternatively romanised as " Ekaterinburg ", is the fourth - largest city in Russia and the administrative centre of Sverdlovsk Oblast , located in the middle of the Eurasian continent , on the border of ___MASK3___ and ___MASK45___ . At the 2010 Census , it had a population of 1 , 349 , 772 . Siberian Federal District (" Sibirsky federalny okrug ") is one of the eight federal districts of Russia . Its population was 19 , 256 , 426 ( 72 . 0 % urban ) according to the 2010 Census , living in an area of . The entire federal district lies within the continent of ___MASK45___ . The West Siberian Plain , also known as Zapadno - sibirskaya Ravnina , is a large plain that occupies the western portion of Siberia , between the Ural Mountains in the west and the Yenisei River in the east , and by the Altay Mountains on the southeast . Much of the plain is poorly drained and consists of some of the world ' s largest swamps and floodplains . Important cities include Omsk , Novosibirsk , Tomsk and Chelyabinsk . The Ural Mountains , or simply the Urals , are a mountain range that runs approximately from north to south through western Russia , from the coast of the Arctic Ocean to the Ural River and northwestern Kazakhstan . The mountain range forms part of the conventional boundary between the continents of ___MASK3___ and ___MASK45___ . Vaygach Island and the islands of Novaya Zemlya form a further continuation of the chain to the north into the Arctic Ocean .