They are among 11 posted so far which also include scenic routes in south west England, East Anglia and Wales.
National Rail, the official rail travel information body, said its "stunning high-definition footage” was “the most comprehensive and high-quality ever shot on Britain’s railways.”
It said the West Highland Line footage “encapsulates the tranquillity of Scotland’s valleys and lochs that make up one of Britain’s most dramatic train journeys”.
The videos of the line, around 45 minutes each, feature the Mallaig-Glenfinnan section, Glenfinnan-Rannoch including the Glenfinnan Viaduct, Spean Bridge-Rannoch over Rannoch Moor, and Rannoch-Crianlarich.
National Rail said a survey last September found 55 per cent of people polled found the scenery the most enjoyable part of train travel and 24 per cent said the movement of the train gave them a sense of calm.
Jacqueline Starr, chief executive of the Rail Delivery Group industry co-ordinating body, said the videos were part of the rail industry’s biggest campaign for a generation, Let’s Get Back on Track, to encourage people back to rail travel following the easing of Covid travel restrictions.
Face coverings will no longer be mandatory on trains and other public transport in Scotland from Monday.
Ms Starr said: “Featuring the world-famous Glenfinnan Viaduct, we want these rarely-seen views of the West Highland Line to inspire people to get back on track and enjoy the best of Britain.
"As well as showcasing Scotland’s extraordinary natural beauty, taking the train is more than just a journey as it connects people to the places they love and is one of the greenest ways to explore the Highlands.”
Ms Starr added that encouraging people to travel by train was also good for the economy, pointing to research by WPI Economics which she said showed leisure passengers travelling pre-pandemic in Scotland by rail spent £2.9 billion on leisure travel.