The original route that stretched a further few miles down to Winchester was scheduled as a Beeching closure in the 1960s, but survived until 1973. Four years later a group of enthusiasts got together to purchase the 10 miles between Alresford and Alton, and by 1985 the line was open to paying passengers for a 20-mile round trip through the quiet countryside.
These days Alresford station is preserved in 1940s Southern Region style. Then, the train service enabled local watercress growers to get their produce to London markets, but now the station is a popular destination for families from London, since Alton is on the main line to Waterloo via Woking.
Some station staff wear period costume and issue tactile, chunky, cardboard tickets that later get clipped with a satisfying kerchunk by the guard. There are flags and whistles and, of course, swirls of steam puffing out of some impressive engines. If you have pounds 200 to spare, the railway company can even organise what it calls a Footplate Experience for you, letting you drive a locomotive and live out those schoolboy train-driver fantasies.
The sturdy locomotives on the Watercress Line have to pull carriages up to the highest station in southern England at Medstead and Four Marks. The jointly named station sits at 630 feet and is one of two stops along the journey. The other is at Ropley, home of the engine shed and workshops.
We got off here to lots of activity. Engines were being fixed by men in blue boiler-suits and there was an accumulated patina of grease over the workbenches. A heady concoction of serious engineering smells from a bygone age met the noses of soft city types while bearded volunteers banged away at cogs and rods.
At Ropley you can get up on a grassy bank that overlooks the station. From here you get a good view of the topiary on the platform of a station set in the 1950s. Well-tended bushes, cut into artistic forms, dwarf the waiting daytrippers. It is a peculiarly English sight.
You can break your journey at any time because your return ticket is valid all day. We had a mooch around Alton to find lunch. The same watery conditions that favour watercress cultivation have also, happily, favoured the brewing trade, although today Alton retains just one brewery, an outpost of a large drinks company.
Poking around the town, we came upon a house, just below the market square, where the poet Edmund Spenser had lived. I knew that not far away in Chawton, Jane Austen had scribbled away a few years of her life, but I didn't know that this sleepy corner of Hampshire could claim another literary connection.
"What did he write?" asked one of my children.
"The Faerie Queen."
"What's it about?"
I had to admit I did not know, so, obviously, it was time to get back on the rails. The children didn't seem to care that I couldn't answer many technical questions about railways. I could rely on nostalgia to paint a picture of the excitement of steam travel when I was a lad and, if you really did want to find out everything there is to know about boilers then someone at Ropley engine shed could explain it to you. But, failing to answer English Literature questions caused me some embarrassment. Back in Alresford I felt the urge to buy watercress and we set off to find the beds, on the other side of town near the Pond. We never got that far, and ended up looking for a greengrocer instead.
The town feels prosperously pleased with itself. A main road no longer cuts through the Georgian main street and now there is hearty conversation outside antique shops, booksellers and fashion boutiques. Alresford does not buzz, it hums like a well-tuned Rover. No wonder film crews come to Alresford and the Watercress Line to make period dramas. The railway details are carefully maintained, the view from carriage windows is rural England circa 1930, the comfortable world of Thomas The Tank Engine and his friends.
The Mid-hants Watercress Line operates throughout the year except during January and November. June, July and August are the busiest months and the service runs daily throughout August (for details, visit: www.itoeye.co.uk).
Thomas The Tank Engine and friends are on the line from 7-15 August. Special trains can be booked in advance. Fares cost pounds 8 for adults, pounds 6 senior citizens, pounds 5 children (under fives free) or pounds 24 families, and you can reach Alton by South West Trains from Waterloo via Woking. Alresford can be reached by bus from Winchester (01962 733810)