HO scale (in North America, Japan, and Australia, and sometimes in Europe,
including the UK) is the most popular scale of model railway in most of the English-speaking and non-English-speaking world.
In H0 scale, 3.5 mm (0.14 in) represents 1 real foot (304.8 mm); this ratio works out to about 1:87.086. 
Rails are usually spaced 16.5 mm (0.650 in) apart which models the standard railroad gauge of 1,435 mm (4 ft 8 1/2 in).

HO Gauge Model Train Scenery
Fences, Roads, Highways,Lamps etc.