The stories and the guide was a good way to bring extra life to the history and provide a good overview of the main historic points. However, they weren't clear how much extra time you had at the end (the start of the tour they implied that you'd have all the time you'd like) and we found ourselves really caught off guard and didn't get to nearly everything we wanted. It's good that the only people in are those on the tour, but if you like to read the plaques or take lots of photos, you'll likely be pressed for time. There's no advantage to coming early - especially if it's cold as you'll be waiting outside and limited seating.
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