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Hi all! I'm planning a trip to London this coming December, probably around the first week or so, and I was wondering what there is to do there. Are there things I can't miss or things I want to skip? I am a young adult, and I enjoy culture, so what museums are best? Are there any cool Harry Potter-related exhibits to see?

Hopefully some of you will have been there, live there, or know what's to do.

Thanks!