This book presents an innovative and detailed study of the ports of the Crown of Aragon in the initial stage of the maritime expansion of medieval Catalonia, comparing them to the Tuscan coast and port-city of Pisa in the decades that witnessed the apogee of its power in the Mediterranean, and looking for common, or contrasting, traits and patterns of development. The approach is multilevel and multidisciplinary, stressing geomorphological, geographical, political, and commercial factors, and drawing on archaeological investigations as well as published ad unpublished historical documents.