The flysch located between Zumaia and Deba is one of the most valuable treasures of all the Basque Coast, and it is considered as one of the most spectacular and famous in the world. The 6th of May of 2010, the International Commission of Stratigraphy recognized it as “a world referent to the history of Earth”. They are authentic sheets of sedimentary rocks that form an open book about 60 millions of years of geological history of earth. Many geologists all over the world gather annually in this place searching for data for their studies. The panoramic is very impressive, the flysch can be appreciated both in the vertical walls like in the ground. It is a fun place to go with children.