The Harry Potter films made the Jacobite Steam Train passing over Glenfinnan viaduct one of the "must see" views when visiting the North West Highlands of Scotland and I couldn't miss the opportunity to grab a photo. The location is easily reached from the main visitor car park although it gets extremely busy, even when I visited in October, so arriving early for a parking space is a must. Timing is key, checking the timetable to make sure what time the Jacobite Steam train is running and equally important, which direction as usually the engine only pulls in the direction of Mallaig, it's not nearly as photogenic with the engine pushing. The autumn colours around Fort William make for a more photogenic shot too so I'd highly recommend visited then if you can.
https://www.landscapephotographyuk.com/scotland-photos