Work has been under way to repair Lithgow's historic James Street rail bridge, with work scheduled to continue into next year.
The bridge, which was constructed in 1869, is the second oldest stone arch railway bridge in New South Wales still in use.
It has been recognised for its state significance "as a rare and highly intact historic sandstone arched railway bridge" by the NSW Office of Environment and Heritage.
"When John Whitton was denied funds to continue with bridge construction using the expensive, imported wrought iron girder bridges, he chose to use stone arch viaducts for his major bridge works. The James Street bridge is a typical example," the assessment of significance states.
Only the James Street bridge and a slightly older Stonequarry Viaduct at Picton still carry mainline railway traffic.
Maintenance and repair work on the St James Bridge began on November 4. The road will be closed until November 18 but works are scheduled to continue in some form until April 3, 2020.
"Sydney Trains is investing close to $2 million to improve the condition of the James Street bridge. Maintenance work includes repairing the heritage sandstone bricks, deck strengthening and controlling water seepage which supports the railway tracks," a Sydney Trains spokesperson said.
Road coaches will replace the NSW TrainLink Dubbo XPT and Bathurst Bullet services over the weekend of November 9 and 10 due to trackwork at multiple locations between Blacktown and Lithgow.
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