Hello, Clentin,
Very cool poem. I actually felt the rhythm of the train while reading. Love that final line!
Thank you,
L

Leaving on a train, a journey untold
Through valleys, mountains, my story unfolds
The whistle is blowing, its haunting cry
I bid farewell, the world passing me by

The windows frame scenes of a fading town
A whirl of colors, reflections abound
Infinite moments, captured in a glance
I chase the horizon, taking my chance

The rhythmic clatter of iron on steel
Echoes the pounding, of my heart, I feel
Leaving behind, what once was so dear
I embrace the unknown, conquer my fear

Two word changes and a couple of little words excised, and you will notice a difference.
The two instances of a nine count will not be noticeable.
Sometimes, a word may fit the meter, but it doesn't seem to fit comfortably with its neighbors.

As always, use it, abuse it or lose it, my comments and advice are free. ~ Geez.
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1] kaleidoscope - too many syllables

2] leave off the [I] in the last line

3] add [so] to the line of "Leaving behind what once was [so] dear"

4] delete [As] last line of second stanza

5] delete the [and] in last line.

I was mistaken in thinking that there were two words to be changed.
~ Geez.
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