Today we bought the Porto Card which offers discounts on admission to many of Porto's most popular attractions. All while trying to avoid the crowds in town for the Redbull Air Race!
Today we spent 60 Euros.
Another reminder to do your research. We discovered that our visit coincided with the Redbull Air Race and the banks of the Douro were filled with people watching the daredevil pilots weave through the race course. We, however bought our city cards and got discounts to a few museums, but discovered that during the race many of the sites closer to the river were free anyway.