After our Rick Steves Portugal tour is over, we plan to day trip with a guide to northern Portugal towns. Has anyone done this, and to what places? We prefer not to go to super-touristy places.
Honestly, I don't know what "touristy" means to people. To me, that would be kitschy places with inauthentic buildings and activities. If you mean very busy places, a lot of Portugal is extremely busy.
We stayed in Braga a few nights and did a day trip from there to Guimaraes. I highly recommend both places. Guimaraes is a UNESCO world heritage site with a castle, very interesting churches and a medieval city center. It is considered a birthplace of Portugal and very historic.
Braga is a very beautiful city, main "attraction" is Bom Jesus do Monte. It also has a very walkable city center, city gates and a cathedral worth visiting.
I'm assuming the tour goes to the Douro River.
EDITED TO ADD: If you haven't found Julie Dawn Fox's website, it's excellent. https://juliedawnfox.com/