An Extra Three or Four Days in Portugal

North of Porto are Guimarães and Braga.

Guimarães is the birthplace of Portugal and has a wonderful town center and 10th-century Castle. And Braga has the amazing Bom Jesus do Monte. These two cities will take up 2 of your 4 days and are an easy day trip from Porto.

I second Gail's recommendation. This spring, we stayed in Braga three nights and visited Guimarães. We enjoyed both cities, Guimarães was charming even in the rain.

Thank you Gail and Jules. We are looking forward to the trip and appreciate the advice. We will check out both. Rob

My husband and I just returned from two weeks in Portugal and Porto was our favorite of the five cities we visted. There are many things to see and do there. We stayed across the river in Vila de Gaia and walked everywhere. My recommendations:
Taste of Porto Food Tour
Base - an outdoor bar.

Bahalo Market--if you take Taste of Porto food tour, you will start here
Porto Cathedral - even if you don't go inside there are lovely views. And the buskers up there were amazing.
Nightlife on both sides of the Douro River.
We didn't take the river cruise but I heard it is wonderful.
Have a fabulous time!

Cross the upper section of Luis I Bridge from Porto to Vila Nova de Gaia to watch the sunset at Jardim do Morro. There is a grassy hill where people gather with friends to enjoy the evening and views.

And our favorite activity was wandering the streets looking for Street Art/Graffiti. Porto and Gaia are great places to view these expressive creative works on buildings and back alley pedestrian paths. https://www.wheregoesrose.com/street-art-porto-portugal/

The big blue cat https://www.collater.al/en/perspentico-liqen-porto/
and the rabbit are my favorites which I think everyone should see :)
https://www.atlasobscura.com/places/half-rabbit/

Jody,
Thank you for the recommendations.

Gail,
Thanks for the websites.

We will research them all!

Thanks Again...Rob