Image caption Thomas the Tank Engine harks back to the age of steam

Thomas the Tank Engine creator WV Awdry, born 100 years ago, set his railway engine stories in a sort of British Atlantis called Sodor. But where is it?

In Sodor they are celebrating, according to the latest book in the Railway Series of stories started by the Reverend Wilbert (WV) Awdry in 1945.

In the book written by WV Awdry's son Christopher and marking the centenary of his birth, the engines - after the usual crop of mishaps - transport a bust of their creator to the main station of Sodor where the Fat Controller supervises its unveiling.

But how do you get to Sodor, home of Thomas the Tank Engine and the other locomotives, the Fat Controller and the Troublesome Trucks?

According to WV Awdry, who died in 1997, it's easy. The Jubilee Bridge at Barrow in Furness actually goes there, he and his brother George wrote in their 1987 book The Island of Sodor. However, ordinary maps say it goes only to Walney Island.

So when you have crossed the bridge, instead of Vickerstown on Walney, you are in "Vicarstown" - gateway to Sodor.

But Awdry himself admitted that Sodor was an afterthought.

In 1950, he writes in The Island of Sodor, after his first four Railway Series books had been written, that he was poring over maps to "find a suitable location for the Fat Controller's Railway and map it... standardise the scenery at any given spot, and so avoid troublesome questions".

A preaching engagement on the Isle of Man made him aware that its bishop is officially Bishop of Sodor and Man - Sodor being an old name for the Hebrides whose ecclesiastical link to Man had long lapsed.

So was born the new Sodor, stretching almost from Furness to Man and described with gentle wit and in enormous detail by the Awdrys in their 1987 book.

But to go there, you need not cross the bridge at Barrow and hope that it will miraculously materialise like a British Atlantis. All over Britain, you find parts of Sodor.

The Talyllyn Railway

The narrow-gauge former slate railway running inland from Tywyn in mid-Wales was the world's first preserved line, its society being formed in 1951. WV Awdry was one of its earliest members.

Image caption WV Awdry, his son Christopher and grandson Richard on the Talyllyn Railway, 1982

"He came and volunteered for the first time in '52. He and his family had a fortnight's holiday in Tywyn and he worked as a guard," says David Mitchell, the line's former managing director.

"And that of course was the famous occasion when they left the tea lady behind, which got written into one of the stories.

"He used to come and oil fishplates and work on the track and things like that in his younger days. And when he died he left us the contents of his study which we have recreated here."

The Talyllyn Railway and its engines are the basis for the Skarloey narrow-gauge railway in WV Awdry's books - the first ever railway in Sodor.

Ravenglass and Eskdale Railway

Image caption Sodor scene? Small engines on the Ravenglass and Eskdale Railway

The scenic narrow-gauge line which carries visitors in open carriages from the Cumbrian coast to the slopes of Scafell Pike inspired the Arlesdale Railway in the Awdry series.

WV Awdry's first book on the line, Small Railway Engines, includes a visit by the Thin Clergyman (himself) and the Fat Clergyman (his friend the Rev Teddy Boston, who had a railway running round the grounds of his Leicestershire rectory).

Three of the Arlesdale engines - Rex, Bert and Mike - are named after the Ravenglass and Eskdale engines River Esk, River Irt and River Mite.

"It is not difficult to this day to still identify most pages with various sites on the line," says the railway's general manager, Trevor Stockton.

A second book in the series, written by Christopher Awdry, is about Jock the New Engine - based on the line's fourth locomotive, Northern Rock.

The Brighton connection

Awdry says in The Island of Sodor that his best-known creation, Thomas, is a class E2 0-6-0 tank engine from the London, Brighton and South Coast Railway; the Fat Controller acquired him as a result of some nifty accounting following World War I.

Image caption Thomas (left) from a stamp marking WV Awdry's centenary, and the E2 engine on which he is based.

Very few of the E2 class were built, and even fewer have the forward extension to the side water tanks which Thomas has.

Thomas first appeared in the second Railway Series book in 1946, in which he is employed moving the carriages for the trains at a big station.

That station with its double arched roof looks quite like Brighton, which would make sense for an engine from the LB&SCR.

Other definite links

Sodor's Culdee Fell Railway is a rack railway - so steep that the trains have cogs underneath which catch on a toothed rack running up between the rails for extra grip.

Image caption China clay engines Alfred and Judy (the model for Bill and Ben) on the Bodmin and Wenford railway

Britain's only rack railway is the Snowdon Mountain Railway, which was visited by Awdry and his friend Teddy Boston in 1963.

Cornwall's Bodmin and Wenford Railway is home to Alfred and Judy - the inspiration for Awdry's china clay engines Bill and Ben.

Both worked at Par docks near St Austell where they shunted china clay wagons to the wharfs.

Other possibles

Awdry loved railways large and small. All lines, bridges, stations and engines contributed to the inspiration of the stories. If you have a memory of a railway scene that reminds you of Sodor, it's likely that Awdry saw it too.

Image caption Thomas and the other engines watch Awdry's bust being unveiled

He grew up at Box in Wiltshire, and is supposed to have got the idea of engines talking ("I CAN do it. I WILL do it....") from the sound as they puffed up the incline on the Great Western line nearby.

Box is near Bath, one end of the Somerset and Dorset Joint Railway - among the most fondly remembered of Britain's lost lines. It is tempting to find the letters SO DO R in the railway's name. But Awdry gives no hint of it, nor do SD&JR enthusiasts claim it.

But then, the rest of us will never know everything the Reverend Awdry knew about Sodor.

Thomas and His Friends, No 42 in the Railway Series, is published by Egmont.