Generally, the area is totally awesome to ride. Certainly you must be in good shape and have endurance when it goes up for long stretches, but when it goes up, so it goes down again! Here are two really good links if you want to try out the Spanish cycling routes.
Here you can quickly find inspiration for your next challenge. We have put our own routes into this site.
They present themselves as follows: "We are more than 450,000 members who explores and shares more than 700,000 tracks" There's plenty of inspiration! A very nice, website. Easy to grasp and inspiring. Want to find great routes - whether you are mountain biking "off piste", or for racing bike on country roads - then this is a great place to discover great new paths and routes.