I think they try to operate year round with weather conditions favorable. You should call the reservationist if you are not sure before you make the trip. ( 800 872-4681 ). I know some of the fall and winter trips can be very enjoyable.
I believe they stop after Christmas and open back up in the spring, due to inclement weather. I would confirm with them.
I don’t have a definite answer but I think so. I know they do the “Polar Express” train rides around Christmas.
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