There is a mini-train like this in Wenatchee (WA) River Front Park. When I was a kid, it was in Saunders Pear Orchard in Peshastin, WA. We would take school trips out there in Grade School, and Mr. Saunders (who built it) would give us all a ride. I think you can still get rides at the new location.
Ok, I found a link. It is a bit bigger than that one:
https://www.youtube.com/watch?v=O7B
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