The wagon, designed by Thrall, a Chicago-based company, operates by transporting the trailers - but not the cabs - of articulated lorries.
The limited amount of freight currently transported by rail is moved in containers with no wheels attached. They are not immediately ready for the road when they have completed their rail journey.
The new wagon, known as the EuroSpine, has taken more than three years to design and will begin operations in the new year between Glasgow and London, on the route operated by English Welsh and Scottish Railway.
The project to design the wagon has been run by Piggyback Consortium, made up of around 40 rail companies. The consortium has been working with four wagon designers for some years and Thrall was the first one to complete the project.
"This is the first time it has ever been done in Britain," Lord Berkeley, chairman of the Piggybank Consortium, said yesterday.
He estimates that by 2003 approximately 400,000 trailers will be transported this way, 5 per cent of the freight transported by road between London and Birmingham. However, Lord Berkeley said the forecasts were cautious.
The wagons will be most competitive with road haulage on long journeys and for the time being will only be able to carry low height but heavy loads, such as steel, because of the height of many of the bridges over Britain's rail network.
The bridges are approximately 6 inches too low. "We're pushing Railtrack to raise the bridges," said Lord Berkeley.
The Piggyback Consortium is in discussions with Railtrack over the cost of project of raising the bridges between the Channel Tunnel and Glasgow, which Lord Berkeley argues will cost pounds 100m and which Railtrack puts closer to pounds 300m. European and government subsidies are available to fund the project.