In Lysekil, you can do quite a lot as a tourist in the summer. You can visit Havets Hus, the house of the ocean, which is an aquatic museum that has most of the different ocean animals and plants living around the coast. If you are the beach type, you can go to Pinnevik, a nice local beach, which offers a good sand beach that is child friendly.
You can take a walk in Stangehuvud, a nature park located not far away from Pinnevik. On these rocks there grows an amazing amount of different plants. In the summer there is even a guide.
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