Sweden
In the summer take a boat to one of the 24,000 islands - even if it's just for lunch. One of the best nearby islands is Grinda which has a restaurant on it.
Get a boat from central Stockholm out to the island of Vaxholm (about an hour away). Vaxholm has cafés, shops, and an old fort museum that you can go and visit. It's a great day trip for a sunny day. You get to see a lot of Stockholm from the water on your way out.
Waxholmsbolaget also runs boats to loads of other islands - their website has good English pages telling you about them.
The ferries go from Stromkajen near the Grand Hotel. Look for the Waxholmsbolaget sign.
www.vaxholm.se/turism/eng/index.asp
www.waxholmsbolaget.se/
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