Rječina is a river in Croatia which flows in the Adriatic Sea in the city of Rijeka (Fiume). It is about 19 km long, with average width of 9-16 m. It springs from the cave on the height of 325 m above sea level, under high cliff of Kičej hill (606 m above sea level). Until 1870 the river's spring was under the next by hill called Podjavorje, but it collapsed in earthquake near village Klana. The most noticeable confluents are Sušica, Lužac, Zala, Zahumčica, Golubinka, Ričinica i Borovšćica but they are mostly dry through the year. In 1968 a dam was built for the needs of hydroelectric power plant, and lake Valići came to existence, but the same name village ceased to exist. Rječina flows through the canyon almost half of her length.
During history this river has been many times border between different states. First time this has happen between XIII and XVI century when it formed the border between Lands of the Crown of Saint Stephen and Habsburgs. Similar thing has happened in 1868 when Rječina became border between Croatian and Hungarian part of Austro-Hungary. After World War I it became for a very short time the border between Free State of Fiume and Kingdom of the Serbs, Croats and Slovenes. After Free State of Fiume was annexed by Italy, Rječina became border river of this country. After World War II Rječina was no longer a border between states.