The Udy (also: ''Uda'', russian: Уды, uk, Уди) is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

that rises in

Belgorod Oblast Belgorod Oblast (russian: Белгоро́дская о́бласть, ''Belgorodskaya oblast'') is a federal subject of Russia (an oblast). Its administrative center is the city of Belgorod. Population: History At the turn of the 17th cent ...

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

and runs through

Kharkiv Oblast Kharkiv Oblast ( uk, Харківська́ о́бласть, translit=Kharkivska oblast), also referred to as Kharkivshchyna ( uk, Ха́рківщина), is an oblast (province) of eastern Ukraine. The oblast borders Russia to the north, Luhans ...

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 ...

. It is a right tributary of the

Siversky Donets The Seversky Donets () or Siverskyi Donets (), usually simply called the Donets, is a river on the south of the East European Plain. It originates in the Central Russian Upland, north of Belgorod, flows south-east through Ukraine (Kharkiv, Don ...

near

Chuhuiv Chuhuiv ( uk, Чугуїв) or Chuguev (russian: Чугуев) is a city in Kharkiv Oblast, Ukraine. The city is the administrative center of Chuhuiv Raion (district). It hosts the administration of Chuhuiv urban hromada, one of the hromadas of ...

.Уды

Great Soviet Encyclopedia The ''Great Soviet Encyclopedia'' (GSE; ) is one of the largest Russian-language encyclopedias, published in the Soviet Union from 1926 to 1990. After 2002, the encyclopedia's data was partially included into the later ''Bolshaya rossiyskaya e ...

Its length is . The drainage basin occupies . The second largest city of Ukraine,

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine.Lopan The Lopan (Russian and Ukrainian: Лопань) is a river that rises in Belgorod Oblast of Russia and flows across the Russian-Ukrainian border into Kharkiv Oblast where it joins the Udy in Kharkiv. The river is long. The river Kharkiv K ...

Physical geography

The source of the river begins with springs in one of the beams

Central Russian Upland The Central Russian Upland (also Middle Russian Upland and East European Upland) is an upland area of the East European Plain and is an undulating plateau with an average elevation of . Its highest peak is measured at . The southeastern portion o ...

near the village Bessonovka

Belgorodsky District Belgorodsky District (russian: Белгоро́дский райо́н) is an administrative district (raion), one of the twenty-one in Belgorod Oblast, Russia.Law #248 Municipally, it is incorporated as Belgorodsky Municipal District.Law #159 It ...

(

) at an altitude of 190 m above sea level. The river crosses the border with Russia to the northeast of the village of Okip in

Bohodukhiv Raion Bohodukhiv Raion () is a raion (district) in Kharkiv Oblast of Ukraine. Its administrative center is the town of Bohodukhiv. Population: On 18 July 2020, as part of the administrative reform of Ukraine, the number of raions of Kharkiv Oblast wa ...

. From the source to the confluence of the river

Lopan The Lopan (Russian and Ukrainian: Лопань) is a river that rises in Belgorod Oblast of Russia and flows across the Russian-Ukrainian border into Kharkiv Oblast where it joins the Udy in Kharkiv. The river is long. The river Kharkiv K ...

flows from north to south, and below - in a south-easterly direction. The Udy flows into the river

Siverskyi Donets The Seversky Donets () or Siverskyi Donets (), usually simply called the Donets, is a river on the south of the East European Plain. It originates in the Central Russian Upland, north of Belgorod, flows south-east through Ukraine (Kharkiv, Don ...

825 km from its mouth. Within the Kharkiv Oblast it flows along

Bohodukhiv left Bohodukhiv ( uk, Богодухів, russian: Богодухов - ''Bogodukhov'') is a city in Kharkiv Oblast (province) of eastern Ukraine. It is the administrative centre of Bohodukhiv Raion (district). Bohodukhiv hosts the administratio ...

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine. Chuhuiv raions and through the city of Kharkiv. The total length of the Udy River is 164 km (127 km within the Kharkiv Oblast). The catchment area is 3894 km2 (in the Kharkiv Oblast 3460 km2). The total height difference (from the source to the mouth is 105 m, the average river slopeis 0.64 m/km. On the river there are cities Zolochiv and