Portugal

I spent 4 days in Lisbon and I'm a big fan. I don't know if you'd need a full 3 days in Porto though.

Some highlights:

Pastel de nata- it tastes like creme brulee in a flake birds nest pastry cup and it is delicious. I'd recommend eating as much of it as possible!

Carmo Barracks

Mercado di Liberia (I think it also goes by the Time Out Market of Lisbon)- great food market with tons of vendors

Walking tour of the city with Sandemans.

Visit the Alfama district of the city

We Hate Tourism Tours X Day Trip- this was a great way to get out of Lisbon and see the surrounding areas. Highly rated on TA as well https://wehatetourismtours.com/lisbon-tours/x-day-trip/

Make sure you buy the tins of sardines as a souvenir!

If you are going to lisbon, i recommend staying on the hill kind in the sao jorge castle area. everything is within reasonable walking distance.

Make sure to make a day trip to sintra to see the moorish castle, pena palace, and quinta de regaleria. It was cloudy when i went but on a clear day there's a beautiful view of pena palace from the top of the moor castle. lots of great history. I didn't go to porto. just drove the algarve cost and some northern country.

Portugal is an amazing place, you'll have a blast!

Lisbon is one of my favorite cities. I wish I could give you specifics but we just wandered around and dropped in random places.

Please come back here and post a detailed review with lots of pictures