|usage = main
|Specifies that a railway is a main line, presumably heavy traffic, often double tracked and/or electrified, may be high speed.
|Used on these elements
|Status: de facto
|Tools for this tag
The tag usage=main is used together with railway=* to map a main line: a railway with higher traffic and higher speed than branch lines, often double tracked and/or electrified, may be high speed, usually longer than a branch line.
|A track is either tagged with usage=main or with service=*, not with both.
Inside a railway station area, use usage=main only for the main tracks (not for siding, yard tracks etc.). That also applies for crossover or overtaking tracks outside of the railway stations, which are mapped with service=*
Other values of usage=*:
|Branch line, less traffic and lower speed than main lines, often single tracked and/or not electrified, may be constructed to lower specifications than main line. May connect a place to a mainline or serve to connect mainlines, typically a few dozen miles in length.
|Tracks in private use that serve only freight transport inside ports, industrial complexes or mining areas, and for connecting these to the public network
|Tracks for military use, mainly on military areas, munitions storage areas or connections to the public railroad network.
|Tracks used for testing of new vehicles or new rail transport technologies.
|Tracks for tourists, around museums, historic or "heritage" trains, often only on weekends and holidays and/or seasonally, most preserved railways (railway=preserved and railway:preserved=yes)
|Tracks at spaceports, deep space radiotelescopes, etc.