Motorists have been warned to prepare for restrictions on one of the county's busiest A-roads which may last up to five years.
Norfolk County Council is reducing the speed limit from 60mph to 30mph on the A140 near Alysham from next month until January 2029.
The restrictions are being imposed because of major works being carried out in the area to provide infrastructure for wind farms off the Norfolk coast.
A line of cables is being laid through the countryside to connect power to the grid.
They will come ashore at Happisburgh and snake across Norfolk to Necton, on the A47, crossing just north of Aylsham, past Reepham and to Dereham.
The works will involve major construction work, with massive trenches dug, to allow the powerlines to be buried in.
READ MORE: Three Norfolk wind farms sold to German energy giant for £1bn
A series of depots are being built along the route.
The reduced A140 speed limit will be in place for 1,162m of road near the junction with Banningham Road, north east of Aylsham.
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