 An intensive and popular train service was operated, but the long tunnel sections with frequent steam trains were smoky and heartily disliked.The network paralleled the North British Railway routes in the area, and after nationalisation of the railways the line declined and was closed in stages from 1959 to 1964.In 1979 the central part of the route was reopened as an electrically operated passenger railway, the "Argyle Line"; this was greatly popular and enhanced connecting routes to west and east made this a valuable link through the city once more.