Police are reminding drivers using the main Peel to Douglas road, a 30 miles-per-hour speed limit is in force around the Mannifest site until Monday morning.
Entrances from the main road to the parking, camp-site and festival field at Glen Lough are all on the Ballahutchin straight.
Organisers have refined access plans to try and prevent traffic queues as thousands of people descend on the site for the weekend music, arts and family festival.
Inspector Will Campbell is in charge of policing Mannifest 2012:
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