Wilderness statistics along with maximum straight line distances to a road.

OK, I dug up some more info. Here it is.

A study from the UWC gives the maximum distance of 15.4 miles from the nearest road (jeep, dirt, gravel, paved, any road) in the Desolation Canyon-Book Cliffs Complex that I mentioned earlier.

This figure is also given as 15 miles in Wild Utah (Falcon series) on roadless areas, and mentions the furtherest point from any kind of road in all areas. The Falcon "Wild Series" is the source of all information below:

Utah:
Book Cliffs-Desolation Canyon Complex-15 miles from the nearest road.
The Maximum from a road on public land was 11 miles from a road in the Uinta Mountain Wilderness.

Wyoming:
Yellowstone-Greater Yellowstone has a maximum distance of 8.1 miles. This was bested by several areas in Wyoming including the Fitzpatrick Wilderness with a maximum distance of 12.8 miles from a road, and the greatest distance in Wyoming.

Colorado: The greatest distance in Colorado was 8 miles in the Weminuche Wilderness in the San Juans.

Montana: In the Absoroka-Beartooth Complex, just north of Yellowstone and which Granite Peak is a part of has a maximum distance of 13 miles, the Second greatest in Montana. However, all these areas are by far bested by the Bob Marshall Wilderness Complex with a maximum distance from the road of 38 miles making this the greatest distance by far (assuming the figure in the book is correct)!

Idaho: Does anyone have the book Wild Idaho? I don't and can't check the statistics.

It is doubtful that there are any greater distances other than the mentioned states in the lower 48.