The Freedom Train: why a train?

I have been wondering why some references to a "Freedom's Gate" in culture have taken on the form of a Train. This is one of the things which cannot be an ancient symbol per se. So how did it enter Consciousness?

a) Why can't it be simply a train, and does it have to be a Stargate reference?
It depends on how this train interacts with the rest of its environment, and how it is framed. And in all these cases, it does act as a Symbol - being in the centre of attention, and a vehicle for certain feelings & emotions to do with a change in perspective, an escape from limitations, etc.
b) Maybe all of these people are just referencing each other?
It is possible, especially in this day and age of speedy information. But even so, the question remains "who was first?" and "what was behind THEIR specific way of framing the symbol?" - and why do we keep getting all these "Freedom" trains (which obviously do work separately, on each individual level where they are referenced)?

I think the answer may lie in American history - the abolishing of slavery, in particular. I was pointed to this answer by the story of the song Rock Island Line, about the train which smuggled slaves to freedom.
Likewise, Martin Luther King Jr. held his speech about using Faith to carve a tunnel in the mountain of despair.

The Symbol of the Train is not used just to escape one condition, but also to visit others: think of the Hogwarts express, for example, taking the students of Magic to another dimension where they are to be trained.

It is also a symbol of the Inevitable.

A variation of the Train would be the Underground or Subway (affectionately called Tube in London), which is even closer to symbolizing Stargates (which are supposedly tubes): it quickly connects different places in the city.

Happy birthday Bilbo and Frodo Baggins

Nephew Frodo & uncle Bilbo Baggins, Stargate dudes extraordinaire!* 

Here is a song in honour of the journey which begins at this time: Sissel, Pokarekare Ana (a World War I love song redone with Maori and Norwegian lyrics). Watch this space for the full explanation of the New Zealand Maori synchronization with Celtic beliefs.

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* Ralph Bakshi animation, 1978: I like this picture very much because, regardless of whether or not we've imagined the characters to look like this, I feel it expresses their "spirit" exactly. It also expresses a curiosity I notice time and time again: films made in the '60s and '70s (but not limited to those time periods) are incapable of transcending their respective current hairstyles, no matter that they are films about an ancient world, the 1700s, the 1920s, or a Space-age future: the same fashions are invariably "back in style"! Of course, this is only if we take it literally. Figuratively speaking, I believe it serves as a nod to certain things in our culture which, thus displaced, are re-examined in a new light.

I also like the picture because it reminds me of the book's funniest indirect physical characterizations (i.e. through the words of another character): "I've made an imitation of your head with a brown woollen mat, Mr. Baggins".