Chorley flying arches: Historic railway feature to be rebuilt
Work has begun to rebuild 16 Grade II listed arches over a railway line in Lancashire.
The arches at Chorley were built in 1841 across the main line between Manchester and Preston to support the retaining walls in a cutting.
They were removed in 2008 to allow stabilisation work to be carried out.
John Johnson from Network Rail said: "The arches will be built back up by hand on the new steel girders - they'll still retain their heritage feel".
An English Heritage spokesman said: "It is believed these are the only surviving example left of this rarely used but elegant solution to such a problem.
"There was concern that these incredibly rare arches could have been lost forever to enable electrification of the line to take place, but English Heritage and Network Rail were able to devise a solution together."
The arches are being rebuilt as part of a £400m scheme to electrify the line.
Work on a tunnel means the line between Leyland and Chorley will be closed for six weeks.
Mr Johnson said: We've inherited a Victorian railway where the tunnels are not suitable for electrification - they're just not big enough.
"Engineers will lower the track to allow the cables to be installed, and to run electric services between Manchester and Preston by 2016."