Wow, what a fun trip this will be, the snow is GREAT this year mate! Yes, the roads are plowed however there is more to know; between October and April it can storm regularly, the roads to this cabin are usually cleared within a few hours after a storm. Since it's on the mountain and at about 2200m (7600ft) elevation you will need four wheel drive. Between December and March you need a real four wheel drive- the car hire company may try to give you an "all wheel drive" sedan car- NO! you need an SUV that can actually go in the snow. :)
No the roads are not always plowed, you never know because itbis illegal to rent for short term stays and the owners dont want you calling anyone on the mountain for help or they will get in trouble for breaking the rules.
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