 The Lanarkshire and Dumbartonshire line was originally proposed (in 1891) to run through Dumbarton to Aber Bay, near Ross Priory on the east shore of Loch Lomond.This would have closely followed the North British line in the confines of the valley of the River Leven.The duplication aroused considerable opposition from residents and shareholders, and the compromise had been reached that the section of the existing line from Dumbarton to Balloch would be made joint.