The Júcar (Spanish: [ˈxukaɾ]) or Xúquer (Valencian: [ˈʃukeɾ]) is a river on the Iberian Peninsula of Spain. The river runs for approximately 509 km from its source at Ojuelos de Valdeminguete, on the eastern flank of the Montes Universales, Sistema Ibérico. Its most important tributary is the Cabriel.