The Welsh Marches Express is running from Paignton to Shrewsbury, taking passengers from various points in the south west up to Shropshire's county town via the scenic route from Newport.
The train will be pulled by an express engine that once plied its trade between London and Scotland.
A4 class No. 60007 Sir Nigel Gresley was built in 1937 for the London and North Eastern Railway, and was named after the man who designed both it and the world-famous Flying Scotsman.
In 1959 it set the fastest postwar speed for a steam locomotive when it reached 112mph in Lincolnshire before being withdrawn in 1966.
Now owned by the Sir Nigel Gresley Locomotive Preservation Trust, it returned to steam at Locomotive Service Limited's Crewe workshop in September 2021 after a six-year overhaul.
It will be resplendent in British Railways express passenger blue, a livery that was used in the early 1950s, but has been regularly worn by the loco since the 1990s.
It's a long day for passengers, with the train departing Paignton at 5.45am. For those wanting to see the train as it makes its way through Shropshire, the timings are:
Hereford - 11.13am-12.03pm
Lemonister - 12.18pm
Woofferton - 12.25pm
Bromfield - 12.32pm
Craven Arms - 12.38pm
Marsh Brook Level Crossing - 12.44pm
Dorrington - 12.54pm
Anyone planning to see the train can follow its progress here.
After a break in the county town of nearly three hours the train will head back towards the south west. Leaving Shrewsbury at 3.50pm, it will traverse the same route, and is due to pass through various locations in the county at:
Dorrington - 4.02pm
Marsh Brook Level Crossing - 4.15pm
Craven Arms - 4.20pm
Bromfield - 4.25pm
Woofferton - 4.32pm
Leominster - 4.39pm
Hereford - 4.56pm-5.31pm
Anyone wanting to see it head south can track its progress here.
From Hereford it will continue south until it reaches Newport where it will head through the Severn Tunnel and down into Bristol, returning to Paignton at 10.13pm.