El Corte Inglés

One-stop shopping at this central department store
Word to the wise: Pick up a 'Carta de Compres' at the Information Desk, use the stickers to mark everything you want to purchase and pay for it all in the basement. If you're from outside the EU you can do this tax free for EUR 6.

El Corte Inglés is Spain's largest department store and your absolute best bet if you need to pick up anything from adapters to socks to another carry-on in which to stash all of your new goods.
The nine-floor store in Plaça de Catalunya is surprisingly easy to navigate. As well as the things you'd expect to find in a department store, there is also a supermarket, pharmacy, optician, foreign exchange counter, travel agency and a beauty salon.

Shop your way to the top floor and reward yourself with a drink and a bite to eat in the café La Rotonda.