Exactly in the middle in the north of the Iberian Peninsula is the autonomous Spanish region of Cantabria (Cantabria). It is not really a tourist stronghold and also not at all south Mediterranean in terms of climate - but: Atlantic. We would not recommend the coast and beaches at this point - the buildings are a bit peculiar, similar to the neighbouring Basque country, and not necessarily beautiful or romantic. The hilly hinterland on the other hand has its charms. And its karst. Perhaps the most unbelievable that there is anywhere in Europe. Nowhere else there are so many and enormous cave systems in such a small area. In total, there are caves of more than 1000 km (!) - with several systems apassing the 100 km with differences in altitude up to 1000 m. Caves < 10 km are so numerous that they almost disappear in the statistics! What is special about this region is that many of the large systems allow traverses: i.e. in at the top and out at the bottom. Pull through the rope, like doing canyoning. Not to mention, that due to the southern location the caves are rich in decoration!