Sidings are the passing places of single-track railroading: one train pulls into the siding and waits while the other holds the main. Their length sets the practical train length on a route, and many Class I sidings run from about 7,000 to over 12,000 feet. In CTC territory the dispatcher controls the switches at each end, and a train too long for the siding forces a more complicated meet.
We're 9,800 feet and the siding at Elm only holds nine thousand, so we'll have to hold the main for him.
When the dispatcher says a siding won't hold you, your train is longer than the siding and a different meet plan is coming.
Also heard as
- passing siding
- passing track
- the hole
Related terms
In the hole
In the siding, waiting for another train to pass on the main line.
Hold the main
To stay on the main track during a meet while the opposing train takes the siding.
Saw-by
A meet at a siding too short for the train that has to take it, so the two trains work past each other in stages.
Main line
The principal track or tracks of a railroad between terminals, where trains need authority to run.