What would you recommend to see in Lysekil. We will be there the first week in September on a cruise for about 8 hours or so.
So you've booked a cruise to visit a number of places that you know nothing about? What led you book that cruise and have you done any research on your own?
It would also be a lot easier to give advice if you told us a bit more about yourself and what you are interested in.
But if anyone else finds this thread in the future, my general advice for Lysekil is Havets hus. It's an aquarium that shows what life is like in Skagerrak in general and in the nearby fjord, Gullmarn, in particular. And if you have the time you can also take the ferry across the fjord to Fiskebäckskil.