Cecil Andrus was Governor of the State of Idaho and later became Secretary of the Interior. I met him last year. Frank Church was a senator from Idaho, and Idaho's largest wilderness area is named after him. This is the largest roadless area in the lower 48 states. My great grandfather was an Idaho State senator and was also postmaster for the state, many years ago.
Largest in the USA is Gates of the Arctic in Alaska. Largest in the lower 48 is Frank Church River of No Return in Idaho and NOT "Death Valley Wilderness in California" as falsely reported elsewhere in Wikipedia.
Another name for a remote bush area could be wilderness or backcountry.
The area of Pepperbox Wilderness Area is 91.297 square kilometers.
The area of Siffleur Wilderness Area is 412.14 square kilometers.
The area of Emigrant Wilderness is 454.369 square kilometers.
The area of Havasu Wilderness is 72.038 square kilometers.
The area of Sylvania Wilderness is 74.167 square kilometers.
The area of Innoko Wilderness is 5,018.102 square kilometers.
The area of Clearwater Wilderness is 57.433 square kilometers.
The area of Raggeds Wilderness is 263.013 square kilometers.
The area of Chamisso Wilderness is 1,841,319.672192 square meters.