dsf, my wife and I have used our 28ft 5th wheel with a slide-out since 1988 to go skiing. This is the second trailer, a 1998 model and I pull it with a Dodge Cummins Diesel which gets about 12 mpg towing. We live in Ohio and have gone West every year for three weeks. New Mexico has RV parks in the towns of Santa Fe and Taos. It is 12-16 miles from the trailer to the ski areas, so we use our truck which has 4wheel drive, seldom needed.
In Colorado we stay in Breckenridge at Tiger Run, large indoor swimming pool, cable at the trailer, a four-star resort. For Aspen we stay in the Basalt KOA 20 miles from Snowmass. In Utah we stay at a trailer park in Sandy, about a half hour to Snowbird/Alta via back roads, Park City/The Canyons an horur via freeway or Brighton/Solitude 45 minutes.
If you are in Pennsylvania or NY state, Seven Springs in PA and Holiday Valley in NY have electric hookups for RVs. To go to Colorado it takes us two full days of travel one way but it is worth it.
To do Winter camping you have to winterize your RV. Our present trailer has the water tank in the basement and the holding tanks in the sub-basement, both heated by piping from the furnace. Using an electric heater will not protect the tanks unless you put a light fixture in there. I use a 100 or 300 watt bulb depending on the temp outside, but furnace propane heater is best.
I also fastened an indoor/outdoor thermometer inside and snaked the outdoor bulb into the basement so I can check the temp there from inside. If your holding tanks are exposed on the underside or only lightly insulated, Camping World sells self stick heating pads which automatically switch from 110v to 12v when needed.
Work with the water in your tank and when it gets low just fill with the hose and take the hose away, also with dumping the tanks, when done put the hoses away since they will freeze and break on you otherwise.
Except for a few times when we had really bad weather, traveling is OK especially since we get books-on-tape from the library to listen to while we drive...
Anything else you want to know, ask...