Z-gauge is the smallest of the operational railway modelling scales commonly available.  It has strong following in the USA and Germany, despite the relatively high prices for the micro-trains.

Z-gauge equates to 1:220 ratio scale, or 9mm in wargaming scale.  It will however fit with both 1:200 scale models and 10mm wargaming figures, even though those are also slightly different sizes from each other.

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