The above link (or http://tinyurl.com/5m9eqo) will take you to a Google My Map of the Street View sightings in Spain. The information is in Spanish, but the information given is very detailed. The purple camera icons, when clicked, will display a photograph of the Street View Astra found at that location. The blue pins will display information on the sighting. Along with Madrid, Barcelona, Sevilla, and Valencia, there is one blue pin near Zaragoza, another major Spanish city.
This is an amazing map. I highly insist you check it out. If you cannot read Spanish, you can use Google Translate to read the placemarks on the map.
Also, Zaragoza has been added to the list of upcoming Street View locations.