Costa de Deba en el Geoparque de la Costa Vasca Nature · Deba, Debabarrena / Bajo Deba, Gipuzkoa The coastal platform towards Zumaia, with cliffs over 150 metres high and flysch formations, forms part of the Basque Coast UNESCO Global Geopark, declared in 2015. Geoparque declarado en 2015 Photo: Jörg Braukmann (CC BY-SA 4.0) What to see and do in Deba