We just did this cruise and Haugesund is a bit of a bore. Not much to do so I suggest you plan something ahead. The tourist train was ok but expensive. We did see the midnight sun but maybe August it will be gone. We did a trip with Calm Giant in Alesund. Excellent-I can't say enough good things about it. We saw fabulous waterfalls and thick snow. Iggy the owner was our guide and a very funny guy he was. Look at his website for more info. Olden is beautiful, try and get to the glacier if you can. Not much doing in the other places so plan your time well and be aware that you have a long walk into town in Trondheim. Shuttles are 20$ each.