Police are pleading with motorists to stick to the one-way system over the TT fortnight.
Work is being carried out today to turn the Mountain Road one-way between Barrule Park in Ramsey and the Creg-ny-Baa - it'll close from 9.30am until 4.30pm.
It's something that happens every year - and something that still catches out both visitors and locals:
Detective Inspector Mark Newey says the problem is exacerbated by SAT NAV systems telling people they can drive onto the course.
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