With the train not due to leave until 13:40 I would normally have got up relatively early checked out and tried to see some more of the city, but Zaragoza isn’t big and I had pretty much exhausted the tourist sites, so instead I had a nice long lie-in and a late breakfast before checking out a little before midday and making my way to the bus stop.
I caught the bus over to the train station where I had a bit of a wait before the fast AVE train back to Madrid and then the local commuter train out to the airport and the flight home.