The Cornalvo Dam is a Roman gravity dam built to supply water to the Roman colonia of Emerita Augusta –present-day Mérida, Spain–, capital of the Roman province of Lusitania. It was built in the 1st–2nd century AD as part of the infrastructure which supplied water to the city. The earth dam Roman concrete and stone cladding on the water face is still in use.

The dam is part of the Archaeological Ensemble of Mérida, which is one of the largest and most extensive archaeological sites in Spain and that was declared a World Heritage Site by UNESCO in 1993.

• List of Roman dams and reservoirs
• Roman architecture
• Roman engineering

• Arenillas, Miguel; Castillo, Juan C. (2003), "Dams from the Roman Era in Spain. Analysis of Design Forms (with Appendix)", 1st International Congress on Construction History [20th–24th January], Madrid

• Aranda Gutiérrez, Fernando (2006), Las presas de abastecimiento en el marco de la ingeniería hidráulica romana. Los casos de Proserpina y Cornalbo (PDF)
• Hodge, A. Trevor (1992), Roman Aqueducts & Water Supply, London: Duckworth, pp. 89f, ISBN 0-7156-2194-7
• Schnitter, Niklaus (1978), "Römische Talsperren", Antike Welt, 8 (2): 25–32 (29)
• Smith, Norman (1971), A History of Dams, London: Peter Davies, pp. 43f, ISBN 0-432-15090-0

• Media related to Cornalvo Dam at Wikimedia Commons