This was a 12 span single track girder viaduct over the River Nethan. Known as 'The Big Brig'.
It was originally a 6 timber arch viaduct, signs of the timber arches are betrayed by the two notches on either side of the piers.
Wear and tear was obvious by 1862 and the viaduct was rebuilt and modified into a girder viaduct. The railway line was chiefly a coal conveyor at this time, it was 1866 before it opened to passengers. For the rebuilding additional metalwork piers were added between the stone piers. The track height was raised 9.5ft which eased the approach from either side. A 20mph speed restriction applied over the structure.
The line closed in 1953 and the viaduct was demolished in 1955.
The metalwork and girders have been removed but the stone piers remain standing.
The the north was Southfield Junction and to the south Little Gill Signal Box.
Southfield No 15 Signal Box
Little Gill Signal Box
Auchenheath New Pit
Southfield New Pit
Southfield Old Pit
Fence Colliery Signal Box
|Location names in dark blue are on the same original line.|
|/ /1861||Lesmahagow Railway|
The Nethan Viaduct was showing signs of severe wear and tear. Later the Camp Viaduct (Ferniegair) was also showing wear. Both were rebuilt. Camp Viaduct is still in use as part of the Hamilton Circle line.