Work is being done on one of the island's busiest stretches of road from 21 October.
The Esplanade, westbound, is being resurfaced, which is expected to take until 29 October to complete.
Officials say improvements on some sections of the road were last made two decades ago.
This will be the third year that work has been done, as a different lane is being worked on each year.
It has been decided to do the resurfacing during the school half term holiday to minimise travel delays, but islanders are still being advised to give themselves more time for their journeys.
Drivers from the east who want to use the Patriotic Street car park are advised to use Castle Street as an alternative.
Kensington Place and West Park roundabout will also be closed off to people travelling westbound, and diversions will be in place at Rue du Galet and St Aubin's Inner Road.


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