The capital of Aragon has plenty to see in do thanks to two thousand years of history and two cathedrals, one of which the massive Basilica del Pilar is worthy of seeing, if just for its massive size. But the Goya frescos inside are the icing on the cake. There's also a Goya museum where you can see some of his smaller works including etchings.
The Aljafería Palace, the northernmost Muslim palace in Europe is also a big draw along with the Roman remains.
Highlights
Basilica El Pilar with Goya Frescos
Aljafería Palace
Station stroll ideas
Delicias station is around 3km from the historic centre and surrounded by busy roads and an average suburb. However, the Tourist Information Office have come up with some ideas for walking and cycle routes
The main sites are on this map.
There is also a walking route that takes you around the bridges to see how the city has coped with the Ebro over the ages: https://www.zaragoza.es/sede/portal/turismo/post/de-puente-a-puente
Cycling
If you fancy a cycling tour, you could try Bizitour
For a cycling route around 'Green Zaragoza' including its iconic Parque José Antonio Labordeta:
https://www.zaragoza.es/sede/portal/turismo/post/pedaleando-por-otra-zgz
For more details on the parks: https://www.zaragoza.es/sede/portal/turismo/post/paseando-por-el-parque
Guided tours
https://www.zaragoza.es/sede/portal/turismo/post/visitas-guiadas
Luggage
Getting there
Zaragoza is easily accessed by high speed trains from Madrid and Barcelona in less than an hour and a half. It takes more like two hours from Pamplona and three hours from San Sebastian.
Useful links
Tourist Info: https://www.zaragoza.es/sede/portal/turismo/?locale=en
If you fancy an alternative souvenir, why not pick up a t-shirt from Dacapo, a local enterprise working on issues of social justice.