I decided to request a few addresses at the Postcrossing official site after not sending for a while, and I got this nice postcard from Spain in return. It shows a little village in the north-east of Spain, near to France, but was sent from Barcelona. Alt Urgell, the region where Aravell is located, is a comarca (county) in Catalonia, a modern representation of part of the historic County of Urgell (ca 789 - 1413), seat of the Counts of Urgell and the historic region of Urgellet.
And the Spanish Christmas stamps was used! Thank you, Luis!