Editing Track gauge (section)

{{Short description|Spacing of the rails on a railway track}}
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{{Sidebar track gauge}}
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In [[rail transport]], '''track gauge''' is the distance between the two rails of a [[railway track]]. All vehicles on a rail network must have [[Wheelset (rail transport)|wheelsets]] that are compatible with the track gauge. Since many different track gauges exist worldwide, gauge differences often present a barrier to wider operation on railway networks.

The term derives from the metal bar, or gauge, that is used to ensure the distance between the rails is correct.

Railways also deploy two other gauges to ensure compliance with a required standard. A ''[[loading gauge]]'' is a two-dimensional profile that encompasses a cross-section of the track, a rail vehicle and a maximum-sized load: all rail vehicles and their loads must be contained in the corresponding envelope. A ''[[structure gauge]]'' specifies the outline into which structures (bridges, platforms, lineside equipment etc.) must not encroach.