A branch line is a secondary railway line. It is a more important route, usually a main line. A very short branch line may be called a spur line. David Blyth Hanna, the first president of the Canadian National Railway, said that although most branch lines cannot pay for themselves, they are essential to make main lines pay.
- Hanna, David Blyth, Macmillan 1924
- Dow, Andrew, Dow's Dictionary of Railway Quotations, JHU Press 2006