We bought the last tour early and got back late 15 minutes after it started. They were very nice at the front, said no problem, and escorted us to catch up to the already started tour. This is a grim COLD place with many hallways/sections to see before you are taken to the big room with the Victorian metal architecture and skylight. Interesting to me to find out that it was the jail used in the movie "In The Name of the Father" with Daniel Day-Lewis, then the tour guide explained that it has been used in numerous films and shows! Incredibly moving. Note that the tour takes you out to the courtyard also (it was raining and he did not deviate from the course!) so be prepared in case you need an umbrella.
Very informative guide, hop-on hop-off buses stop right outside and there's a tiny cafe for light snacks and drinks. We enjoyed it and would recommend as something to see!
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