The bridge was opened in 1970 at a cost of �11m

It represents the latest in a long history of improvements to the 10-lane Kingston Bridge which arches over the River Clyde in Glasgow and is central to the city's road network.

The cantilever bridge opened in 1970 after councillors on Glasgow City Council decided to extend the M8 motorway - which links Edinburgh to Glasgow - into Glasgow and beyond.

The ambitious project cost just over �11m and took three years to complete.

As the British public's love affair with the car grew, more and more traffic began using the structure on a daily basis.

Today the 50,000 tonnes road bridge is reputed to be the busiest in Europe taking some 155,000 vehicles per day.

KINGSTON BRIDGE FACTS Built between 1967 and 1970 Opened by the Queen Mother in June 1970 Cost just over �11m The Scottish Executive is responsible for the bridge Glasgow City Council is in charge of the current �31.5m project 180 sophisticated devices monitor movements of the bridge In 1970 it took 31,000 vehicles a day, today it takes 155,000

That volume of traffic has necessitated a number of projects to strengthen the structure.

The challenge to keep the bridge open while carrying out more than �31m of vital improvements has been left to engineers and planners at Glasgow City Council.

Users of the bridge have become used to the sight of road traffic cones over the years.

One particular project to strengthen the structure saw six years of restrictions to lanes and vehicle weights.

There had also been a number of weekend closures for work which could not be carried out while traffic was crossing.

'Minimum of disruption'

When engineers found the bridge was leaning, they closed it twice in 1999 in order to lift it 20mm.

The structure was then supported for seven months while new concrete piers were constructed.

The latest project of repairs involves demolishing and rebuilding the Stobcross off-ramp at a cost of �4m.

To carry it out over the next 20 weeks, it has been necessary to close the West Street on-ramp - which takes an average 3,000 vehicles per hour - for access and safety reasons.

ON-GOING WORK Reduced lanes and weight restrictions between 1994 and 2001 Closed over two weekends in October 1999 for lifting work Weekend closures in the summer of 2000 West Street on-ramp to the Kingston Bridge closed February 2003 for 20 weeks

On the latest work, Councillor Alistair Watson from Glasgow City Council, said: "This kind of traffic management is very important, so it is vital that we get it right.

"I would appeal to people be patient, plan your journey and give plenty of time and also use other forms of transport."

About �250,000 has been spent on diversions and project leader Marshall Poulton believes there will be a minimum of disruption.

He said it made economical and environmental sense to chop the ramp into three metre sections, load them onto lorries, take them away to be crushed and rebuild a new structure.

But if drivers think that the ramp work will spell an end to cones and closures on the Kingston Bridge they will have to think again.