Work to repair Newport Arch in uphill Lincoln will begin in two weeks’ time.
On September 23, a specialist stonemason will restore damaged areas of Newport Arch, one of the UK’s oldest still used by traffic, and Town Wall.
They will also add an extra layer of stones to create a protective barrier on the stones exposed at the top.
As previously reported, the City of Lincoln Council were able to carry out the work due to a £60,000 Heritage Fund grant from WREN.
The work is essential after winter frost and wet winters caused damage, plus general corrosion over the years.
The project is one of the largest since a lorry crashed into the arch in 1964, part of the reason the arch is on English Heritage’s “at risk” register.
Replacement work will be carried out by Robert Woodhead Ltd, who are currently working on repair work in Lincoln Castle.
The work will take eight weeks to complete, but will not cause disruption to traffic.
Arthur Ward, Heritage Team Leader at the council, said: “Newport Arch is one of the city’s most iconic monuments and these works will go towards securing it for future generations.
“We have been working closely with English Heritage and WREN on the restoration to ensure we keep its historical value.
“We appreciate that during the works the necessity for scaffolding will reduce footpath widths around but there will be no disruption to vehicles.”
The project is the first on many Medieval and Roman wall restoration around the city over the coming years.
Ben Robinson, Heritage at Risk principal at English Heritage, said: “Newport arch is a nationally important monument and has been open to traffic for hundreds of years.
“The repair work will ensure that it continues to remain a Lincoln landmark for decades, hopefully centuries, to come.
“Lincoln has a wonderfully rich Roman and medieval heritage, but some of its most important monuments and buildings are vulnerable and at risk.
“We want to see Newport Arch and other sites off the national ‘Heritage at Risk’ register and this work should be the first step towards that goal.”