Segre is a river tributary to the Ebre.

It starts at the Spanish exclave of Llívia, passes through La Seu d'Urgell, Balaguer, Lleida and joins into the Ebre at Mequinenza.

Among its tributaries: Valira, Noguera Pallaresa, Noguera Ribargorzana, Cinca.

See also: Pyrenees