I've never understood why there hasn't been a road to Juneau up to now.
Its simple cost/benefit analysis. Here are a couple clues.
These mountains rise directly out of the water. Every mile of road would have to be blasted out of solid rock. Its just not needed. There is daily ferry and air service down to Juneau.
I'll trust you to take care of Pennsylvania I'f you'll trust Alaskans to take care of Alaska.
Because President Polk wimped out of his campaign promise of "Fifty-Four Forty or Fight!" Had he gotten us 54° 40' as the northern border of Washington as promised, British Columbia would be ours and we would have continuous U.S. territory all the way to Alaska (the southern border of Alaska is 54° 40'). They would have probably built a road through there in WWII.