It looks like you are using adblocking software. I understand that ads are annoying, but this is one way for me to make a living on this site. As an alternative you might consider becoming a donating member. All ads are removed automatically for donating members.
Looks like we are coming down of the Alto de Mostelares (the big hill west of Castrojeriz). The first 800 metres is sealed (concrete?) but its very steep (around 18% - 1 metre down for every 6 metres of travel). From the greenery it looks like late Spring or early Summer. Cheers