Guzmán el Bueno y el ducado de Medina Sidonia Historical milestone · Sanlúcar de Barrameda, Costa Noroeste, Cádiz Image of Sanlúcar de Barrameda, not of the place itself. On 4 April 1295 Guzmán el Bueno received the verbal promise of the lordship of Sanlúcar, officially confirmed on 13 October 1297. His descendants established the county of Niebla in 1369 and attained the title of Dukes of Medina Sidonia in 1445, establishing their permanent residence in the town from 1478. 1295-1478 Photo: Jose Luis Filpo Cabana (CC BY 3.0) What to see and do in Sanlúcar de Barrameda