An old stone bridge near Inverness Airport is to be demolished and replaced as part of an upgrade of the rail line.
Network Rail is planning the project as it paves the way for double tracks to be installed on the route.
The masonry arch bridge lies near to the site where the proposed new Inverness Airport rail station is to be built.
It will be “redecked” because the arch shape can not accommodate two tracks underneath.
A planning application for the £5million station development at Dalcross was lodged earlier this month, with work expected to be completed by December next year, and the station opening in 2018.
Transport chiefs are already drawing up early plans to build a second platform at the station, as well a “passing place” for trains at the new stop-off.
The new bridge would provide space for the double-tracking and also a revamped pedestrian and cycle route linking the thousands of new homes being built at Tornagrain to the station and airport.
Although a separate project, documents lodged with planning application for the new rail station revealed the move to demolish the bridge.
The report said: “The Dalcross footway-cycleway route passes to the east side of the site and provides a pedestrian route across the railway line to the airport terminal.
“Network Rail plan to replace the existing masonry arch bridge on this route with a pedestrian-cycleway crossing.
“The demolition of the existing bridge and replacement is to allow for future double tracking of the rail line.”
The opening of the airport rail station will coincide with the introduction of a new high-speed, hourly service between Inverness and Elgin, and official forecasts have estimated that within 50 years the station will become the busiest in the north, after only Inverness city itself.
Regional transport partnership Hitrans hopes that the Scottish Government will give its initial backing to the more expensive, second phase of the station project by summer 2017, with a view to having it included in the next programme of works between 2019 and 2024.
The station is proposed for a site next to the C1017 airport access road, between the first and second roundabouts after leaving the existing A96, at the southern corner of the airfield.
Under the plans, every train on the Inverness-Aberdeen route will stop at the station.
