Public viewing days at the new prison have been fully booked, with just a few places left on reserve lists.
Phone lines for bookings opened last week and were jammed with people eager to get a sneak preview of the £41 million facility in Jurby.
Senior Officer Karl Christian says all 2,400 places have now been booked for the two weekends in April and May.
He is now asking anybody who can’t make their allotted time to call and let somebody on the reserve list have their place.
(Picture: The prison at Jurby during construction).
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