The Segre (, ; ) is a river tributary to the Ebro (Ebre in Catalan) with a basin comprising territories across three states: France, Andorra and Spain.
The river Segre, known to Romans and Greeks as Sicoris, and to the Arabs of Al-Andalus as Nahr az-Zaytūn (نهر الزيتون, river of Olives) has its sources on the north face of the Pic del Segre or Puigmal de Segre ("Segre's Peak") in the French department Pyrénées-Orientales (historically the comarca of Alta Cerdanya), in the Catalan Pyrenees. It follows a western direction all along the Cerdanya (Cerdagne) Valley, and crosses the town Saillagouse, the Spanish exclave Llívia and Bourg-Madame.
It enters Spain at Puigcerdà and continues west until La Seu d'Urgell, where it meets the Valira River coming from Andorra. From this point it adopts a south-western course across the pre-Pyrenees (with several dams along its gorges) and the western plains of Catalonia. It passes through Balaguer, Lleida and flows into the Ebro at Mequinenza.
Among its tributaries: Valira (from Andorra), Noguera Pallaresa, Noguera Ribagorzana, Cinca.
Segre may refer to:
- Segre (surname)
- Sègre (department), a former department of France
- Segre River, a river in Catalonia
- Segré, a commune in Maine-et-Loire, France
Segré is a commune in the Maine-et-Loire department in western France.
Sègre was a former department of the First French Empire in present-day Spain and Andorra, named after the river Segre. It incorporated Andorra. Val d'Aran, which is in the north side of the Pyrenees, was instead incorporated to the department of Haute-Garonne.
Sègre was created on 26 January 1812 when Catalonia was annexed by the French Empire. Its subprefectures were Talarn, and Solsona. Its prefecture was Puigcerdà; the only prefect was Jean Louis Rieul de Viefville des Essarts, from February 1812 to 1813.
In March 1813 it was merged with the department of Ter into the department of Ter-et-Sègre. This merger was established by decree but never published in the Bulletin des lois, nor endorsed by any senatorial decree, leaving its legal status uncertain.
In 1814 the French left the Iberian Peninsula, having occupied it since 1808. The departments disappeared.
Segre is a surname. Notable people with the surname include:
- Beniamino Segre (1903–1977), Italian geometer
- Corrado Segre (1863–1924), Italian geometer
- Emilio G. Segrè (1905–1989), Italian American physicist
- Luigi Segre (1919–1963), Italian automobile designer