Father Christmas is travelling from Bedford to Brighton and back on a First Capital Connect train.
Santa will be accompanied by his elves and helpers. Children travelling on the train can look forward to receiving free gifts from Santa and enjoying free entertainment from travelling face painters, balloon artists and perhaps a magician or two.
Members of the Rotary Club of St Albans Verulamium will be on board the train collecting for charity throughout the journey.
The eight-carriage train is a scheduled service and will leave Bedford at 10.10am.
The southbound train calls at Blackfriars at 11.20am and London Bridge at 11.27am.
Northbound, the train is scheduled to stop at London Bridge at 1.45pm and Blackfriars at 1.54pm.
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