The Cathedrals Express whistle-stop rail tour to mark The Queen’s 90th birthday is over half way through its four-hour journey through London and Surrey.

Departing from London Victoria just after the scheduled time of 10.10am, the two vintage diesel engines have been spotted across west London as it makes it way to Surrey and back.

This is the first of two celebratory tours taking place on Thursday (April 21) and the train has been admired by train enthusiasts in Hounslow this morning just after 11am.

Disappointingly, the LMS Jubilee Class 45699 Galatea steam train which was due to haul today’s special tour developed a last minute boiler fault and was taken out of service.

In an unfortunate mishap, the original Royal steam train 6201 Princess Elizabeth, or ‘Lizzie’ , also had complications with her repairs and was replaced by the Galatea just last week.

Tonight, the second journey for the London evening tour, to mark the momentous occasion will set off from Windsor and Eton Riverside at 6.13pm, stopping off in Hounslow to pick up passengers at 6.37pm.

Queen Elizabeth II will be celebrating her birthday at nearby Windsor Castle.

Passengers will see unrivalled views of the lights in London as the train crosses the River Thames over Battersea Bridge passing close to famous landmarks such as The Shard, and is due to return to Hounslow just after 9pm.

Elsewhere in west London, Kew Gardens marked the occasion with a tree planting ceremony .