Rail passengers are being reminded to check before travelling over Christmas and New Year as vital infrastructure improvement works take place at locations across Scotland.
Network Rail will complete important track, drainage and signalling work over the festive period in what is a £15m investment to keep the railway reliable for passengers and freight.
Some services will be disrupted by the programme, including Helensburgh and the West Highland Line.
Signalling upgrades taking place at Craigendoran near Helensburgh over the New Year will see services to Helensburgh Central start/stop at Dumbarton Central on January 2 while services from Fort William, Mallaig and Oban will terminate at Crianlarich, with rail replacement buses in operation between Crianlarich and Glasgow Queen Street.
Caledonian Sleeper services on the West Highland Line will not run.