IT was billed as the first real motorway in Scotland - and it opened 50 years ago this week.

News reports said it was probably as important a landmark in Scottish communication history as the Forth Road Bridge, which had been opened two months earlier.

The new stretch of road which attracted so much attention turned out to be just over four miles of the Harthill bypass.

It was declared open on November 20, 1964, by the Minister of State, an Edinburgh MP named E.G. Willis.

It was the first section of some 20 miles of a new M8 motorway planned to replace the existing A8 road between Newhouse and Newbridge.

The A8 itself ran between Glasgow and Edinburgh.

The M8 would in time encompass the colossal new Kingston Bridge as well as the Charing Cross Inner Ring Road, a development that changed this part of the city centre for ever.

The last part of the motorway within Glasgow's boundaries was completed in 1980.

Today, the M8 stretches for 60 miles between Scotland's two main cities, via Renfrewshire, Lanarkshire and West Lothian.

Stuart Baird, a civil engineer behind the authoritative Glasgow Motorways website, describes the M8 as one of Scotland's most important roads.

It transformed vehicle travel across central Scotland, and provided a route that was safe and reliable.

"That four-mile stretch of the Harthill bypass was the first piece of the new M8 to be built," says Stuart. "By this time, the old Scottish Office had a proposal for a new motorway connecting Glasgow and Edinburgh."

The 1960s was a time when planners looked ahead and began work on a network of motorways. Car ownership was on the rise, and the planners also recognised the importance of taking traffic away from old residential neighbourhoods.

Some parts of the old A8 were unsafe. It had three lanes, with a shared overtaking lane, and the high number of fatalities and serious accidents made it clear that something more than just upgrading the road was needed.

What was required was a brand-new motorway along a safer route.

"In Glasgow there was a massive building programme for a good few years," Stuart said. "There were even plans for more motorways, which, however, were cancelled.

"The motorways were designed for traffic flows that were 20, 30 years in the future. Flows were projected as far as 1990 or 2000, which at the time was unknown in forward planning.

"The planners were thinking ahead, but this made it difficult to justify the new motorways. People asked them, 'Why are you building this new eight-lane motorway at Townhead?'

"The planners said the motorways would eventually get up to 120,000 vehicles a day, but the reply would come back - 'Well, we're only getting 20,000 a day at the moment.' Needless to say, a lot of justification was needed at the time."

The planners got their way, and Glasgow now has some 50 miles of motorway within its boundaries.

Stuart's website lists these big construction projects - not just the M8 but also the M80 (which links Glasgow with Falkirk and Stirlingshire); the M77 primary arterial route between Glasgow and Ayrshire; the M74, linking Glasgow with England; the six-mile-long M73; and the M898, Britain's shortest signed mainline motorway.

The Kingston Bridge, of course, is a key part in the M8, coping with vast amounts of traffic every day.

"Since the opening of the M74 completion in June 2011, the Kingston Bridge has levelled out at 165,000 vehicles a day," said Stuart.

"It can flow freely with up to 120,000 - that was the point of its five lanes. With 160,000, that's obviously where you get the congestion, though to be fair, it's the two lanes at the Charing Cross area that are probably more responsible for the congestion on the bridge."

E.G. Willis, the MP who opened that first part of Harthill half-a-century ago, would marvel at the way in which motorways now cut across Glasgow.

"Glasgow's motorways really allowed for the pedestrianisation of Sauchiehall Street, Buchanan Street and Argyle Street," says Stuart.

"Before then, they were the main east-west and north-south routes through the city centre. Bypassing the centre allowed these shopping areas to be taken out of that equation and to be pedestrianised, or even part-pedestrianised.

"The motorways have ultimately created a nice environment in these streets, particularly in Buchanan Street.

"I would say that that has been a pretty successful aspect of the whole motorway programme."

n Website: www.glasgows-motorways.co.uk