<P> The rail loop at Folkestone is clockwise and is in a cut and cover tunnel, while the loop at Coquelles is anti-clockwise . This evens the wear on the wheels of the shuttle locomotives and vehicles, as each set (left or right) spends only half the time at the outer edge of the line traversing the corners . Because of the land space available, the French loading platforms are designed so that they can be entered and exited in two directions and by both freight and passengers . </P> <P> A Eurotunnel Shuttle is on average 775 metres in length and is made from constructive stainless steel . The carriages used for the shuttle have a larger loading gauge than either British or French railways, so that they can accommodate vehicles and the stabilisation equipment used when loading . Consequently they cannot travel outside the tunnel and the two terminals onto the national railways . The carriages are open all the way down when loading but are closed off individually when the train sets off . </P> <P> Passenger vehicles are carried in a car shuttle train, made up of closed wagons . The rear half of the train carries cars and other low vehicles in double - deck wagons, with the first and last two carriages of the section containing the access ramps . Coaches, buses and other high vehicles travel in the single - deck rake at the front of the train . In busy times, cars can also use this section . Eurotunnel occasionally run the double deck carriages at "half full", closing the top deck to reduce costs . </P> <P> Driver and passengers may leave their vehicles and walk along the train to use the toilets, but there are no other services on board . Passengers have to stay in their cars or beside them, as the gradients in the tunnel mean that there are chances when vehicles could roll back and forth and strike someone . The toilets are provided in every third carriage in the double - deck section, and in the first and last carriages in the single - deck section . </P>

How many cars fit on the eurotunnel train