The bridge over the Esla at Castrotorafe Monument · San Cebrián de Castro, Tierra del Pan, Zamora Image of San Cebrián de Castro, not of the place itself. The villa owed its importance to possessing one of the few stable crossings of the Esla, a fundamental link between Castile and Galicia in the Middle Ages; the control of that bridge explains its wall and its castle. Photo: El alistano (CC BY-SA 4.0) What to see and do in San Cebrián de Castro