If you've done Barcelona and Madrid, make your next mini break Spain's third largest city – Valencia.
Located about three-and-a-half hours' drive down the coast from Barcelona, Valencia has a reputation for being an artistic hub; the street art is abundant, the stylish yet eccentrically dressed millennials are plentiful and the impact of a modern creative sentiment on an ancient cityscape has been handled marvellously.
Obviously, being on the beach, the city is more alive in warmer weather, but don't be put off going in winter, too. As well as the excellent deals you can get on accommodation and flights, the temperature doesn't really drop that low (despite what the puffer-coated locals shivering under the outdoor heaters are saying) and there are plenty of cosy tapas bars to drink all the red wine in.
Valencia is sleepier than Madrid and Barcelona, and it makes for a nice change of pace. Walk slowly, take a nap in the afternoon (everything's closed anyway), and spend several hours lingering over each (unbelievable) meal. In short, Valencia is the city break you need to actually relax.