If I had to pick the single most important road in Alaska, I'd have to go with the George Parks Highway. Heck, it might even be one of the top 10 or 20 most important roads in the whole country. For starters, it connects the two biggest cities in the state: Anchorage and Fairbanks. Add in the fact that it's pretty much the only road to access the jaw-dropping Denali National Park, and that its route parallels the historically significant Alaska Railroad, and you've got a solid case for the highway's importance. Plus, it's a really pretty route that has some surprisingly awesome attractions to stop at along the way.
Lodi, California, United States
From Medford - Route 62 north and then east. From Klamath Falls - Route 97 north to Route 62 north and then west., OR, US
Dawson Creek, British Columbia, Canada
Watson Lake, Yukon Territory, Canada
Tok, Alaska, United States
106.8 Richardson Highway (Hwy 4), Glennallen, AK, US
Whittier, Alaska, United States
Seward, Alaska, United States
The route starts just north of Anchorage. This is Alaska's most populous city, and is home to 40% of the state's population. It's also in a particularly stunning location, with the Cook Inlet on one side and the Chugach Mountains on the other. Since it's a major city, it's got loads of world-class attractions (the Alaska Native Heritage Center, the Alaska Zoo, the Anchorage Museum) that you can explore if the natural beauty (Kenai Fjords, Alaska Wildlife Conservation Center) doesn't do it for you. Plus, there's a huge variety of awesome restaurants (brewpubs with restaurants like 49th State and Glacier Brewhouse are always local favorites, but you can find more upscale options with a variety of cuisines as well.)