There is no long term parking at the station itself. However there is parking behind the old post office building (short walk to the station)and they offer a discount parking rate as long as you punch you parking ticket at the kiosk in the train station. Also there is parking in the market st. garage. But be aware if you get back late you may have to call a number posted at that garage and wait for someone to let you in for your vehicle.
There is no "long term" parking at the station. It is limited to like 15 minutes. You would need to use the lot by the old post office. I believe it is called Transit Park. You can the validate your parking ticket inside the train station for a discount on the parking fee.
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