My apartment is well situated in a peaceful neighborhood near city center and Porvoo sights. You walk 10 min. here from bus station or harbor. 5 min walk there is a really good food store with liquor store. There is a free parking on the street.
At Porvoo you can spend time to visit old town museums, shops and restaurants. A great nature reservation area with lots of birds (Sikosaari) is near too. I have a map with tips, so you will find the best places easily.