Zumaia ([s̻umaja], Spanish: Zumaya) is a small town in the north of Spain in the Basque Country.

The town has two beaches (Itzurun and Santiago), which are of interest to geologists because they are situated among the longest set of continuous rock strata in the world. These formations are termed flysch and they date from the mid-cretaceous period to the present, a time period of over 100 million years. The K–T boundary is present at the Itzurun beach, and fossils can be found, notably of ammonites. The strata stretches along a distance of about 8 km, between the beaches of Deba and Getaria, with Zumaia lying in the middle.

The town is also the home-turned-museum of the painter Ignacio Zuloaga. Exhibits include works by El Greco, Rivera, Zurbarán and Goya. Across the street there is a museum of craft and hand-crafted products of Laia. Within the city centre, the Basque-style Gothic church of San Pedro can be found. It has a temple with a magnificent reredos by Juan de Antxieta, the only work by this Basque sculptor found in Gipuzkoa.

Zumaia is located at the point where the Urola and Narrondo rivers come together. The origins of the town can be traced by its ancient monastery. In the Middle Ages, the people who lived in the Sehatz valley having to endure the continuous attacks of pirates and pillagers, fortified the city. The church today retains the relic of its defensive appearance.