Question: what scale are ho trains?
Answer: HO or H0 is a rail transport modelling scale using a 1:87 scale (3.5 mm to 1 foot). It is the most popular scale of model railway in the world. The rails are spaced 16.5 mm (0.650 in) apart for modelling 1,435 mm (4 ft 8 1⁄2 in) standard gauge tracks and trains in HO.