Playa de la Concha Nature · Donostia/San Sebastián, Donostialdea, Gipuzkoa Urban beach 1,350 m long and 40 m wide on average, in the bay of the same name; it is one of the city's defining landmarks. Photo: jeffwarder (CC BY-SA 3.0) What to see and do in Donostia/San Sebastián