Needless to say I did not have a camera handy... It was hauling several carriages and for some reason there was a diesel engine at the tail end of the train, I suspect to provide a backup if it broke down or ran out of coal or something. I'm guessing that the summer steam excursions in and out of Paddington have started again - and it turns out to be The Cathedrals Express, on the route Paddington-Westbury-Yeovil Pen Mill, Weymouth-Southampton-Paddington
Unfortunately it's £100+ per seat, I suppose worth it if you're a steam enthusiast but I made enough long steam journeys in my childhood to satisfy me, I think.
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