'Gauge 3' describes models built to run on track having a gauge of 63.5mm (2½ inches) and to a scale of 13.5mm to one foot. This equates to an overall scale of 1:22.5, the same as that applied to 'G' scale (the commercially-produced popular garden railway scale), the difference being that Gauge 3 models run on scale 'standard gauge' track, whereas the 'G scale' models run on 45mm gauge track (which equates to a scale one Metre gauge, popular in continental Europe). There is a benefit from this relationship between the two systems in that commercially produced model figures, accessories and buildings are suitable for both. You will have noted that the track gauge is 2½ inches and may be aware that there is another society catering for this gauge. The difference between the two being that 'Gauge 3' is a 'scenic' railway standard, whereas 2½ inch gauge is a 'ride behind', model engineering, standard where locomotives (running on simple elevated track) haul passengers around a circuit. 'Gauge 3' is, by a considerable margin, the largest 'scenic' model railway scale. For comparison purposes, 'Gauge 1' models are built to a scale of 10mm to one foot and 'Gauge O' to a scale of 7mm to one foot. For in depth detail of the origins of 'Gauge 3' see the history page and for the principal dimensional standards for track and stock see the standards page.