Train times will change slightly to allow charter trains to share the Cambrian Coast Railway line.
Transport for Wales say they made the changes “for the wider economic benefit of tourists visiting the area”.
A special charter from Shrewsbury to Pwllheli on Thursday, 4 April was caught on camera at Aberdyfi by Cambrian News reader Llinos Furneaux.
A spokesperson for Transport for Wales said: “Following discussions with Network Rail, we have agreed to make minor amendments to our timetable to allow charter services to run, because of the wider economic benefit of tourists visiting the area. Without these changes no charters could run on the scenic Cambrian Coast, despite a long history of such services.
“This will only take place on a small number of occasions each year and always outside of the main peak summer season.”
The train on 4 April was operated by Pathfinder Railtours.
From Shrewsbury it travelled to Machynlleth and Dovey Junction, towards Aberdyfi, north to Tywyn, then Friog and down to cross the Morfa Mawddach estuary on the half mile viaduct to Barmouth.
It then went past Harlech to Minffordd, across the Glaslyn Estuary, on to Porthmadog and past Criccieth to the end of the line at Pwllheli.