Tours are scheduled on an as needed basis for 15/20 minutes at the purchase of a ticket. They are not ran every 15 minutes but your wait time will not be more than 15/20 minutes, sometimes less if someone has already purchased tickets before you.
When i was there it was twenty minutes. That was August 19. Also the train they advertised was broken.
Yeah about every 15 minutes
Every 15 minutes
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