Two hours away from Barcelona you can find one of the most unique hotels in Europe. rooms here are pretty much cubes made from glass. Do not expect to find here TV, furniture or phone - there is just a bed and minibar. And hot spring where water is heated to 36C. It's calming sound will make you sleep like a baby too.
Next door there is two-star Michelin restaurant, and plenty of outdoor options including cycling. Must see!