You may only visit by pre-arranged guided tour, so best to go to the old school and book in on arrival in Castletown, and then see the other attractions (castle, nautical museum) depending on time available. As I was the only visitor, I did not get the benefit of the group Tynwald re-enaction described in other reviews. Instead I had a fascinating discussion with the guide about how the politics of the Isle of Man works which I found most informative. Certainly not to be missed.
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