The Department for Infrastructure is warning people it's out line painting today.
A team will be on the Tholt Y Will road between 9am and 5pm.
It's while the roads are closed for racing.
Spectators for the MGP transiting between the Bungalow and Sulby are asked to be aware and ride with caution.
The DOI has also added the upper parts of the road are unfenced and sheep do wander across the road, so to always be prepared to stop.
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