There are probably very few people in Craven who were fans of Barbara "Red Babs" Castle, whose socialist principles burned as hot as her flaming red hair when she was a cabinet minister in Harold Wilson's Labour government .

As Minister of Transport, back in the days when these people still had proper titles, she introduced the breath test - to roars of outrage - and it has taken some 40 years for most sensible people to accept drunken driving is a grave social evil.

This weekend, however, there will be thousands of people in Craven for a celebration that would never have been born without her: the Skipton Waterway Festival. And I'll wager that not one of them in a thousand knows that Red Babs was their saviour.

The reason: but for her, the Leeds-Liverpool Canal would have been erased from the face of the earth.

I knew Barbara Castle quite well. Her husband and I worked for the same newspaper group and I had often covered her electioneering drives when she was an MP for Blackburn.

And, although I never agreed with her brand of politics, I liked her a lot: the only other politician who fought as gallantly for her beliefs was Maggie Thatcher.

But it was not until Babs retired from politics and wrote her autobiography that I learned some hitherto unpublished facts. The first was that she was a keen narrow boat enthusiast, spending many weekends with friends on the few stretches of the Rochdale Canal still open in those days.

I drove down to the Home Counties to interview her about her autobiography and we were having tea and biscuits, the official interview over, when the subject of canals and their restoration came up.

First came the astonishing revelation that, for years after World War Two, the Government didn't even know it owned the canals. Clement Attlee had, of course, nationalised the railways, but no-one in Whitehall realised that the railways owned most of the canals, having bought them in the 19th century mainly to close them down as potential rivals.

It was almost 20 year later, when long lengths of the canal system had become little more than open sewers after a generation lost in limbo, that Transport Ministry officials hit on the bright idea of filling them in and turning them into roads: this was the time of the motorway building boom, remember.

They did not know that their boss was a secret boater and thought they had come up with a brilliant idea of building new roads on the cheap. There followed a series of scenes straight out of that brilliant TV series, Yes Minister, because - as she admitted to me - she had to come up with a better excuse for throwing out these plans than the mere fact that she spent the odd weekend on the water. Being a woman who did things thoroughly (if only you could say that about some of her successors in high office today) she cast round for advice from other experts and they came up with a gem: the canal system had become an integral part of England's land drainage system.

Fill them in, she was told, and millions would need spending on thousands of miles of new drainage pipes. If not, thousand of acres of good farmland would return to bog. Babs had the weapon she wanted and there was no Sir Humphrey who dared challenge this formidable lady.

So the canal-to-road plan was tossed into the Whitehall gutter and an utterly priceless piece of English industrial history was saved to become a hugely important national resource for leisure, exercise and wildlife.

It may seem unlikely, but this weekend thousands of people at the Skipton Waterway Festival should raise a glass to their absent friend, Barbara "Red Babs" Castle.