Free entry to museums and other attractions with these discount cards.
There are several discount cards available in Barcelona. Find out which is right for you here: Barcelona discount card comparison
If you're under 26 years of age and you're visiting other countries as well as Spain, you may be interested in an ISIC Card from STA Travel.
With the Madrid Card virtually anything you could want to do in Madrid is free - you just have to decide whether you can get them all done in a single day. Read carefully this page on What the Madrid Card Offers
and take a look at the review (below) before buying.
The Seville Card is the most expensive of the four cards - but with so much to do in Seville (and with much of it being quite expensive, it's hardly surprising.
As with the Madrid Cultura Card, this cheaper discount card covers most of the same things as the main Seville Card, but is a lot cheaper.
A cheaper alternative to the Barcelona Card, the ARQUEOticket offers entrance to Barbier-Mueller Museum, the Egyptian Museum of Barcelona, the Maritime Museum of Barcelona, the Archaeology Museum of Catalonia and the Museu d'Historia de la Ciutat de Barcelona.
See also: Barcelona discount card comparison
The cheapest card on offer, the Zaragoza card will get you in free at just about every important sight in town - but with most of them quite cheap in the first place, you'll need a very full day to get your money's worth.
Full-time students (of any age) can qualify for this card, the most famous student discount card in the world. If you are not a student but are under 25 (or are a teacher), scroll down for more cards available to you.
Much like the ISIC discount card, but for the under-25s (whether they're in education or not) and teachers.