Kozacha Lopan [Kozača Lopan’]. Map: III-17. Town smt (2001 pop 5,870) on the Lopan River in Derhachi raion, Kharkiv oblast. It was founded in the 17th century. An important battle took place here at the end of 1918, in which the troops of the Army of the Ukrainian National Republic were defeated, enabling the Red Army to take over the Kharkiv region.