This should be in ASB.
In order to have practical railroads, you need a variety of other inventions to be practical before actual railroads can be used. You need at least steam power developed sufficiently to be of use on sufficient scale, then, you need industrialization on a scale sufficient to manufacture components necessary for large enough railroad construction, and for sufficient number of steam-driven locomotives.
Even if you use alternate method of propulsion (i.e. horse-driven, or otherwise not highly technological propulsion), you severely reduce the usefulness of such railroads, and you STILL need to have good industrial base and empire-wide organization to produce and maintain railroad tracks and stations. Remember, railroad tracks require more frequent maintenance than standard roads, require standardization in production, and require industrial manufacturing capacity to cover sufficiently large portion of the empire, as opposed to craftsman-based manufacturing, or small manufacturing capacity.