 The "latifundia" (sing., "latifundium"), large estates controlled by the aristocracy, were superimposed on the existing Iberian landholding system.The Romans improved existing cities, such as Lisbon ("Olissipo") and Tarragona ("Tarraco"), established Zaragoza ("Caesaraugusta"), Mérida ("Augusta Emerita"), and Valencia ("Valentia"), and reduced other native cities to mere villages.The peninsula's economy expanded under Roman tutelage.