This natural arch was collected by the author during a 10 days hiking trip along Costa de Cantabria between the town of Ribadescella and the villages of Celorio in september 2014. On this gallery, the arches are shows from east to west. There are more opening of the same formation around. This one is probably the most decent shot you can had. Check a great example of these formations to
Arco de Los Bufones 32.