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 93 kilometres (58 mi) long. The river Kharkiv is one of its tributaries.

Lopan
The Lopan in Kharkiv, Ukraine
Native nameЛопань (Russian)
Location
CountryRussia, Ukraine
Physical characteristics
MouthUdy
 • coordinates
49°56′13″N 36°12′12″E / 49.9370°N 36.2032°E / 49.9370; 36.2032
Length93 km (58 mi)
Basin features
ProgressionUdyDonetsDonSea of Azov