The post offices in Spain are called “correos” (www.correos.es). In case you want to send a letter or a postcard you can buy stamps in any tobacco store and just dump it into one of these yellow mail boxes. (Don’t use the green one, that is for the posts own use)

Pharmacies are on every corner and easy to spot in Barcelona. Just watch out for a blinking, green cross, indicating hour and temparature and you’ll find everything to cure your cold or hangover.