The Alaska highway is no big deal. I traveled it
Post# of 2057
It used to be treacherous around Trutch mountain, 30 yrs ago before they moved the highway down to the flats. The biggest danger was hitting a moose at night. As for the river, you can access the Tanana River at Nenana, about 50 miles west of Fairbanks, where the summer barges depart and follow it approx 155 miles north and west til it hits the Yukon River at Tanana, which leads to the Bering Sea, north of Hooper Bay, and follow the coastline to Nome. I read somewhere that the total trip by boat is roughly 500 miles.
The only other option that I am aware of is to take the Sacramento River to Stockton, and follow the shipping Channel out under the Golden Gate Bridge into the Pacific Ocean which is highly inadvisable in a small barge. Lol