Discovering the flysch in the Basque Country

Discovering the flysch rock formations

When walking in the Basque Country, don’t miss the 8km-long coastal stretch of flysch between the towns of Deba and Zumaia in the province of Gipuzkoa.

Zumaia is visited in our guidebook to walking in the Basque Country – your ideal companion for walks in the area.

The coast here reveals some extraordinary rock formations that are now protected as part of the Basque Coast Geopark. Just 30 minutes by car from Donostia-San Sebastián and a little under an hour from Bilbao.

What are the flysch?

The most striking formations are made of what is known as the flysch. These are a sequence of sedimentary rocks that make up one of the longest continuous rock strata in the world.

They were formed nearly 100 million years ago. Waves crashed against the cliffs, creating a platform of alternate hard layers of limestone and sandstone, and soft layers of clay and loam.

The effect, especially at low tide, is stunning.

How to get to the flysch

Park in the bustling, attractive fishing port of Zumaia (Car tour 1 in the book). Start walking from the chapel of San Telmo on the western side of town. It’s perched precariously right on the cliff tops above the beach of Itzurun.

From the chapel some of the best parts of the flysch can be seen by following the GR121. There’s red and white waymarking, part of the vuelta de Gipuzkoa route. It’s just 10 to 15 minutes in the direction of Deba.

Continue along the same coastal footpath for about an hour to the most spectacular section of coast around Sakoneta. This forms Europe’s most extensive abrasion platform. It can be defined as a sloping or nearly flat bedrock surface that extends out from a sea cliff under shallow water.

At low tide, the Sakoneta coastal area reveals a huge variety of wildlife. There are cucumbers, starfish and sea slugs, along with many varieties of sea anemone. The platform has been carved over millions of years by the sea. Wavy, almost wafer-like sheets of bedrock of great beauty have been created.

Until recently this area was hardly known outside the province. But with the creation of the geopark, this is likely to change and so now is the perfect time to explore it.

Guided walks and boat trips

The Algorri Interpretation Centre in Zumaia is a good place to learn more about the flysch. Guided walks to the most spectacular sections of the coast around Sakoneta and beyond start here.

Three-hour boat trips from Zumaia along the coast westwards via Deba to Mutriku are available. This enables the best of the entire geopark to be viewed from the sea.

These trips are highly recommended and can be booked via the geopark website. Alternatively, book through one of the local tourist offices in any of the three towns mentioned above.

This being the Basque Country, you are never far from mouth-watering pintxos (the Basque version of the tapa). Find them in bars in all the towns and villages along the coast. Wash them down with the local txakoli white wine – to help recharge the batteries after an exploration of the flysch route!

Buy our guide to walking in the Basque Country.

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Discovering the flysch rock formations

What are the flysch?

How to get to the flysch

Guided walks and boat trips

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