Le Val des Terres will close for around an hour and a half this evening to allow 'urgent tree works' to go ahead.
Traffic & Highways says an 'unsafe tree' up the Le Val des Terres requires urgent attention, as it poses a potential risk to the public.
The winding hill in St Peter Port will be closed from 6PM tonight (28 January), when services suspect the majority of commuter traffic will have subsided.
Pedestrians and cyclists will still be able to pass through during the closure, and a diversion for vehicles will be in place along Fountain Street and Colborne Road.
The road is expected to reopen by 7:30pm.
Another closure is scheduled to take place from 3 to 16 February for wider tree surgery works.

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