One of the best things about Sanlúcar is its shell-encrusted river beach and warm waters, a couple of kilometres’ walk from the town centre and usually quite deserted. This is flanked, on the opposite shore, by the beginnings of the Parque Nacional Coto de Doñana, whose vast marshy expanses (strictly regulated access) signal the end of the coast road to the west. Visits to the park from Sanlúcar are possible with a boat cruise, which, while it doesn’t allow for serious exploration, is nevertheless a wonderful introduction to this remarkable area. The trip lasts approximately four hours and allows two short, guided walks inside the park to spot wildlife. The Real Fernando – which has a cafetería on board – leaves daily from the Bajo de Guía quay (Mon–Sat June–Sept 10am & 5pm; March, April, May & Oct daily 10am & 4pm; Nov–Feb daily 10am; €16.35, under-12s half-price; booking essential on t956 363 813, wwww.visitasdonana.com). Tickets should be collected (at least 30min before sailing) from the Fábrica de Hielo, Bajo de Guía s/n, the national park’s exhibition centre (daily 9am–8pm) opposite the Real Fernando’s jetty. Also note that binoculars are pretty essential, and, while they can be hired on board, having your own is a distinct advantage.