The Via de la Plata historically starts at the Cathedral in the city of Seville. Seville is part of the autonomous region of Andalusia in the south of Spain. It is possible to get your first stamp on your Pilgrim's Passport in the Cathedral the evening before you start your walk or at the Pilgrim's Mass at 8.30am each day. A credential/passport can be collected at the Pilgrim's Office, though they do prefer that you arrange this online. More information on their website.