Melbourne's long-standing yellow-and-blue train network map is headed for the bin, to be replaced next year by a new, rainbow-coloured map aimed at making it easier for passengers to navigate around the city.

But the new map, a trial version of which has been put on show at just three stations on the Frankston line and at the PTV Hub at Southern Cross Station, lacks key information such as fare zones and whether a station has car parking or a connecting tram or bus.

Part of the new PTV rail map, inspired by the London Underground's world-famous map.

The current Metro map, with its simple two-tone design in which yellow signifies zone one and blue zone two, has been around for several years but will be scrapped in time for the opening of the Regional Rail Link next year.

Public Transport Victoria is already piloting a potential version of the new map, but expects to make several changes following public feedback before officially launching the map.