The branch line to Ballachulish left the Caledonian line to Oban at Connel and crossed the entrance to Loch Etive at a height sufficient to allow shipping to pass. The strong currents prevented the use of piers so a long cantilever span was built, at 524 ft, the longest in Britain after the Forth Bridge. From the outset it was for a single track railway and a narrow roadway.

The bridge was not opened for road vehicles until 1909 and evn then they were obliged to be hauled across on a converted motor charabanc, fitted with rail wheels.In 1913 they were allowed to drive across but only when it was not required for a train. After closure of the railway in 1966 it became part of the A828.

Nearby Connel Ferry station was opened on 1 July 1880, when the final section of the Callander and Oban Railway, between Dalmally and Oban, came into use. The original layout comprised a crossing loop with platforms on either side. Considerable enlargement of the station took place in 1903, with the opening of the branch line to Ballachulish. The original Down platform became an island platform, with the Down Main line routed alongside the new south face, and the Up Main line (the original Down line) to its north. The former Up platform became the Branch Platform and a bay platform was constructed at its west end. A goods loop ran to the south of the Down Main line. A turntable was provided in the goods yard for turning the branch line locomotives.

In 1940, additional sidings were laid in on the south side of the station for the wartime traffic, these being removed in 1948. The Ballachulish branch closed in 1966. The extensive track layout was reduced to just a single line routed via the former Branch Platform (the original Up platform). The island platform was taken out of use. The layout grew again in 1968 when an oil storage depot with two sidings was built on the site of the goods yard. A run-round loop was laid alongside the single line to the east of the station, connected at each end by points controlled from a ground frame. The disused island platform was demolished in 1985.