You're kidding, right? The word would be "unique".
First check out the climate stats on any serious mountain range in the world, compared with summer weather in the Sierra. Or weather any time of year, for that matter. Then consider that the longest roadless stretch on the Appalachian Trail, or anywhere else in the crowded East, is about 30 miles.And that's in the Smokies, where it never feels even that far from the road. The famous Presidential Traverse, in the Whites, is 26, and that passes 3 AMC huts and squirts between the Mt Washington Toll Road and cog railway by only a few feet. On the Continental Divide trail, about 120 miles is the longest roadless stretch. In the Sierra, the PCT runs 209 miles between Tuolumne and Kennedy Meadow, and much longer routes between Tioga Road and Sherman Pass Road are possible without wandering. Add several 14ers, National Parks, etc.
Well, if you may not be fully appreciating what's just down the road from you, try a weekend in July on Long's, or better still, Pike's (hee hee). You'll never wonder again.