I have snowmobiled in, numerous times to destinations to see some country away from others, mostly country I would never be able to see if I had to snowshoe in. Some of these places I may have some noise, but by late afternoon it all goes away. The quietest I have had it, was a trip in N. California into the Caribou Wilderness. I snowmobiled in the 12 miles to the trailhead, put my snowshoes on and bped the 2 miles or less to a cluster of lakes. I barely heard sleds maybe once that day. The balance of the day was very quiet, with some little birds making a little noise. A great night, late winter, warm night, down to freezing was all and me with my 5 degree bag. Another beautiful place is north of Truckee, Perazzo Meadow. Some noise during the day from people using the main road on their snowmobiles and if the wind is right, the noise from I-80. Closer to home, not many people as it is lightly populated and no one else in the backcountry camping.