$15 need to book in advance. Tickets are very limited.
The ticket portal is found at https://tovreacastletours.com/castle-tours/ Tour prices depend on which type of tour you take.
Tickets are $15. They release a large number of dates and times a couple times a year and they sell out quickly and quietly. It took me a year from deciding I wanted to go to actually getting tickets and going. Others on my tour date said it had taken them 2 years.
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