Zaragoza was the farthest city we saw from Madrid as a day trip. 2H fast (expensive) train:

We randomly picked a day that was a huge Christian festival, festival of Pilar. It was fun but also a huge mess, millions of people everywhere:

Basílica de Nuestra Señora del Pilar was beautiful, but it was a total mess with all the crowds:

it's big, but it was packed

We took the elevator to the top, decent views:

Lots of Roman ruins and museums:

they had a nice amphitheatre

lead pipes, yum

Sadly, some things were closed due to the massive festival, which was clusterf a times, not counting all the things that were closed from 14:00 to 16:00 for siesta:

we were forced to stop for a 15:00 lunch

Thankfully a few things were still open:

One of the open things was the very cool Origami Museum (click for its own page):

Eventually we went to the other part of town to visit, we went to Aljafería Palace:

And then it was finally time to take a late 300kph train back to Madrid: