Here is a third type.
Basically the trains
were used since end of 1800 to carry guns and other weapons.
During WW1 special trains
were built in order to carry medium to large naval guns by France, Germany, Italy, ...
Moreover Italian Navy take care to setup mobile coastal defense convoys during ww1 and maintened active these trains
for all ww2, when 12 convoys were used. Moreover one train with Flak was given from Hitler as "personal" present to Mussolini.
To Gollevainen: what do you think to draw the Russian and the Finnish (russian train captured by finnish partisan)???