The route will be shut from 9.30am until 4.30pm
The Mountain Road will be closed during the day today (23 May) to set up the one-way system for the TT races.
The A18 will shut from 9.30am until 4.30pm whilst the works are carried out.
When it reopens, the road will run in one direction from Ramsey Hairpin to the Creg-ny-Baa for the duration of the TT festival period.
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