The Two Major Rivers of the Iberian Peninsula: Ebro and Tagus

The Iberian Peninsula's two most significant rivers—by length, discharge, and historical importance—are the Ebro and the Tagus (Tajo/Tejo).

Ebro (Ebre in Catalan)

• Length: ~910 km (565 mi) – 2nd longest in Iberia, longest entirely in Spain.
• Source: Fontibre, Cantabrian Mountains (Cantabria).
• Course: Flows southeast across northern Spain through the Ebro Basin (Logroño, Zaragoza, Tortosa).
• Mouth: Delta on the Mediterranean Sea (Tarragona province).
• Significance: Irrigation for Spain's agriculture (Ebro Basin), hydroelectric power, unique delta ecosystem.

Tagus (Tajo in Spanish, Tejo in Portuguese)

• Length: ~1,007 km (626 mi) – longest in Iberia.
• Source: Sierra de Albarracín (Teruel, Spain).
• Course: Flows west across central Spain (Toledo), forms part of Spain-Portugal border, crosses Portugal (Santarem, Lisbon).
• Mouth: Wide estuary at Lisbon into the Atlantic Ocean.
• Significance: Water supply for Madrid (via transfer), Lisbon, irrigation, historic trade route, cultural icon (Fado, literature).

Other Notable Rivers

Douro (Duero), Guadiana, Guadalquivir, Minho (Miño)—each vital to their regions. But Ebro and Tagus dominate the peninsula's hydrology and history.