The West Highland Railway was built to Fort William by Lucas and Aird, but there were delays with the West Highland Railway Mallaig Extension (Guarantee) bill for the Mallaig Extension Railway in the House of Commons as the Tory and Liberal parties fought over the issue of subsidies for public transport.

This Act did pass in 1896, by which time Lucas and Aird (and their workers) had moved south.

[1] New contractors were needed and Robert McAlpine & Sons were taken on with Simpson & Wilson as engineers.

[4] Construction of the extension from Fort William to Mallaig began in January 1897, and the line opened on 1 April 1901.

[8][9] It has three arches, with a centre span of 50 feet (15 m), and a radius of curvature of 200 metres (660 ft).