Police have issued one with a fixed penalty notice
Police say they've already had to stop people trying to go against the one-way system on the Mountain Road, with one person having been issued a fixed penalty notice.
Every year it's made one-way for the TT fortnight in the interests of safety.
The Mountain Road is currently closed as today's racing gets underway.
Inspector Paul Kemp says it's something they have to deal with every year:
Arrow returns to service after repairs
A Manx bap and chicken katsu curry included in new school menu
Study finds Isle of Man's clothing offering rates poorly for women
Charity implores people to 'adopt responsibly' as it faces capacity issues