FYI...The specific climb mentioned by the OP is not in the Pyrenees. It's in the Cantabrian Mountains in the north central part of the country. The other notorious climb that has been used in La Vuelta--the Angliru--is also not in the Pyrenees but rather Asturias, which is west of Cantabria. There are a lot of ranges in Spain besides the Pyrenees. In fact, Andalucia is the country's single most mountainous territory and contains the country's two highest peaks.

Spent 7 weeks touring Andalucia BITD. While most of the climbs are not high in altitude, some of the grades will put hair on your chest. Some of the worst grades are the roads leading up to ancient hilltop towns that were built up high for defensive reasons. Saw one grade sign of 16%. Even with a 22x34 low gear I had to walk part of the way into the center of one town. Fortunately, there now often bypasses so that if you don't want to stop in a town you don't have to climb up, ride through the town and then descend back down to keep on your way.