The locomotives were on always the south (downhill) end of the train to prevent runaway trains.
This allowed for efficient routes to be built, and prevented trains from trying to travel the "wrong way" down a section of track.
The signalling was later altered to prevent trains entering the crossing loop simultaneously.
The police said that some protesters had blockaded the tracks to prevent trains from leaving Landquart.
To prevent trains running over a switch too fast several workarounds are in use.
It also prevents such trains from blocking the main line or a platform at Newbury.
Very soon though, practical experience proved that there had to be some way of preventing trains running into each other.
And union officials have asked whether the train had the special brakes that prevent trains from going through red lights.
A computerized block system is used to prevent trains from contacting each other.
In 2005 the points from the main line were spiked, preventing trains from accessing the platform.