A branch line is an offshoot of a main railway line which connects the railway to smaller communities. Branch lines are used to ensure that communities which do not qualify for placement on a main route can still access the railway line, and take advantage of services offered by the railway, such as passenger and freight transport. With the decline of railways around the world, branch lines are rapidly vanishing in many regions.
The organization of railways includes main lines and subsidiary lines. The main lines are established first, connecting major cities and points on the map. Then, subsidiary or branch lines are added in to extend the network of the railway. The main lines are also known as trunk lines. Historically, rapid railway expansion necessitated the quick establishment of branch lines, and railways sometimes competed to connect towns with branch lines so that they could monopolize the demand for railway transport.
An individual branch line is often not very profitable, because not enough people ride it. However, a system of branch lines overall can be profitable, by allowing a railway to service more areas. Passengers tend to be drawn to transit providers who offer broad service routes, which means that the more branch lines a railway has, the more passengers it can attract.
An extremely short branch line is known as a spur. Trains which travel on spurs and branch lines are usually prioritized behind trains which travel on the main line in train scheduling. These trains carry fewer passengers, and are therefore regarded as less critical. These trains are also typically slower, and are required to yield to faster trains when they encounter them.
In some cases, the development of a branch line has allowed a community to flourish, and towns on former branch lines have grown into cities in their own right, thanks to the railroad. Several railroads have also developed by taking over branch lines and using them to establish their own network, especially in areas like the United States, where there are huge amounts of territory to cover, making plenty of room for numerous railway transport providers.
Railway maps may identify branch lines with special insignia to alert passengers to the fact they are branch lines. Scheduling on such lines tends to be less frequent than that on the main line, which can be an important fact to be aware of when planning a trip. For example, while a subway system may run until 2:00 AM, it may close its branch lines at midnight, so someone planning to get home on a branch line would need to plan accordingly.
