Backpacking in Denali National Park and Preserve in the wintertime is rough. Do not try it unless you know what you are doing. Everything in the area pretty much shuts down during the winter months! Do not expect a warm Irish coffee after the backpacking trek through the snow. On the plus side, everything is free! If you can get yourself out there you can go as far as you would like. I only got 1-2 miles from the sled dog kennels as my toes thought it was too cold to venture further. There are limited water supply areas and if you do want them you must be willing to trek a few miles in deep snow to get to them. I should mention that there’s lots of snow during the wintertime just one more time. Be prepared! i visited in October but for some reason can not change it to the proper month.
BUT you also get the chance to see the northern lights so it’s a win.
P.s. these units are very very different during the summer months and very accessible to tourists!