A small section of a major road will close for 48 hours as part of an overrunning programme to create a new junction.
Watling Street, on the outskirts of Radlett, will be shut in both directions at the junction of Harper Lane this weekend.
The closure will come into force from 12.01am on Saturday (January 23), with the road scheduled to reopen by 11.59pm on Sunday January 24.
In addition, there continues to be no access in out of Harper Lane, at the Radlett end, until February 28.
A signed diversion route has been created for drivers wishing to use Watling Street while it is closed this weekend for resurfacing.
The closure of Watling Street forms part of Phase C of the roadworks in Harper Lane.
When the Harperbury Park housing development in Harper Lane was approved by St Albans District Council in 2017, it came with the planning condition that transport links to Radlett were improved.
This led to plans for a cycle lane and footpath on the narrow bridge at the end of Harper Lane, while there is also a minibus which travels between London Colney and Radlett.
As a result of the cycle lane and path, the bridge will become single-file, with three-way traffic lights installed at the junction of Harper Lane and Watling Street.
The work was meant to be completed in December but the developer of Harperbury Park, Bloor Homes, confirmed last month "unforeseen delays" pushed the completion date back to February 28.
Read more: Harper Lane roadworks to overrun by two months
Bloor Homes released the following statement about the Watling Street closure: "Bloor Homes is working closely with Hertfordshire County Council to ensure that disruption and congestion is kept to a minimum for the duration of the works. A diversion will be in place during the road closure.
"Bloor Homes is aware of the disruption the road closure will caused to residents and businesses of Harper Lane and Radlett and we apologise for the inconvenience caused during these necessary road closures."
Meanwhile, there will be roadworks at the other end of Harper Lane, where it meets Shenley Lane, for more than a month.
There will be multi-way temporary traffic lights at the mini-roundabout from February 1 until March 5.
It's not completely clear at this stage exactly what type of work the county council will be carrying out.
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