It's not just little boys who delight in all things mechanical. My daughter Hannah has, at the age of 18 months, developed a fascination with trains, planes and automobiles. And as the perspiring steam engine hissed and puffed its way into Bishops Lydeard station in Somerset, it became clear we'd chosen the right excursion. Her excitement was palpable. "Train! Train!" she squealed, clapping her hands, jabbing her fingers at the engine. It was time to board the Santa Express.
You can't beat a train ride with kids. The journey was suggested by our friends Becky and Nick, whose daughter, Emmeline, is the same age as Hannah. Our Santa Express, tugged along by a steam locomotive, trundled along the track of the old West Somerset Railway in the Vale of Taunton Deane, squeezing between the Quantock and Brendon Hills. Most of the children aboard were aged six to eight or nine. They were remarkably well behaved; few seemed bored.
For those with infants of 18 months and even younger - we had brought our five-week-old son Thomas - the journey is also rewarding. Hannah sat on my wife Lucy's lap, looking out of the window, munching biscuits and being co-operative when it came to photographs.
All that time spent with books that feature farmyard animals paid off: as cows, sheep and horses went by the window, the two girls would look, point and thump the table in general approval. Then Santa appeared. With a few crumbs of pastry stuck in his long white beard this was clearly a working lunch for him. His present for Hannah was a toy panda, and, for Emmeline, a golden bear.
After 30 minutes, the train arrived at its furthest point, Williton. The train paused here for 25 minutes, which meant the girls could scamper around the platform. The return ride was harder work. Hannah took to marching up and down the carriage but her boredom threshold had been breached by the time we arrived back in Bishops Lydeard.
A good feature of such a train ride, for those armed with grandparents and friends to share the load, is that everyone can take something from the day. For the parents, in addition to the sheer delight of seeing your child so happy, it could be the glass of sherry. For a grandparent, it could be nostalgia: opposite us, a grandfather waxed lyrical about the process by which coal propelled the steam engine. His daughter's eyes glazed over long before the sherry arrived.
Though the Santa Express specials around the country usually end today - you need to book three months in advance - there are plenty of other train experiences for children in the UK over Christmas and beyond. The Didcot Railway Centre (01235 817200; didcotrailwaycentre.org.uk) stages a steam day on New Year's Day, when visitors can witness the spectacle of engines billowing smoke as their fire-boxes are filled with coal, and travel in 1930s carriages. The centre is open daily apart from Christmas Day and Boxing Day. Meanwhile, the North Norfolk Railway (01263 820800; nnrailway.co.uk), which runs for 10 miles from Sheringham to Holt, operates Mince Pie rides from 26 December to 3 January, with a pastry and sherry thrown in. Unlike the Santa Express, seats cannot be reserved and visitors pay on the day.
In 2007, there will be no shortage of opportunities to take a day out with Thomas the Tank Engine. The National Railway Museum in York (0870-421 4001; nrm.org.uk) is running a series of Thomas days from 10 to 25 February, while many other venues run excursions aimed at children, as well as other family-oriented events. These include the Embsay and Bolton Abbey Steam Railway (01756 710614; embsayboltonabbeyrailway.org.uk) in the Yorkshire Dales, from where you can walk to the 12th-century priory of Bolton Abbey; the Bluebell Railway (01825 720825; bluebell-railway. co.uk) along part of the classic branch line of Lewes-East Grinstead in Sussex; and the Watercress Line in Hampshire (01962 733810; watercressline.co.uk), a steam railway that once carried watercress - the major industry around Alresford - to London.
The steam locomotives do not have to be big to be beautiful or to appeal to little people; the period railway of Colne Valley in Essex (01787 461174; colnevalley railway.co.uk) offers, in addition to lovingly restored signal boxes, bridges and stations, a miniature railway of particular interest to children.
For more details on special trips on the West Somerset Railway visit wsr.org.uk