Quadruple Track Layouts
As it can be seen from the pictures below in the Gallery of diagrams, the four tracks can be paired either by direction (slow/fast in each pair) or by purpose (speed or direction in each pair).
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Famous quotes containing the word track:
“The weary sun hath made a golden set,
And by the bright track of his fiery car
Gives token of a goodly day tomorrow.”
—William Shakespeare (1564–1616)