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livewithstyle
Since: May, 2016
acer_filia
Since: Jun, 2016
Sumanuil
Since: Jan, 2019
acer_filia
Since: Jun, 2016
donatello-is-the-fellow
Since: Nov, 2014

I recall reading a book as a child that was about a pair of children that entered a magial world through an abandoned subway station. They had tokens that they used to pass through. They befriended amagical creature that I think was a giant turtle or caterpillar that I believe died later in the story? Based on vague memories of how the library was layed out, I would guess it was aimed at 10-13 year olds.