Across the Ebro basin is the centenary book of the Confederación Hidrográfica del Ebro. Through texts by specialists, archival material, and historical and contemporary images, it traces a century of water management from the basin unit perspective. The volume explains how this form of governance was built, what landscapes and uses the Ebro brings together, and why managing a common good remains decisive in the face of the social, environmental, and climate challenges of 2026.