We just finished a 5000 mile round trip BC, Oregon coast, Calif Redwoods, Nevada desert and into AZ and then back to BC.
I have a 2017 GMC Truck that has GPS mapping on a screen in the dash, I have a road / Hwy Garmain GPS that sticks to the windshield I also have a hand held GPS that I use for hunting fishing and ATVing at home. Nothing came close to a good O"ll hand help paper map.
The best place I found to get these maps were at a Walmart stores, Yup even in the USA they have Canadian maps. We bought a great map of BC at a Walmart in Colville Washington State, you will most likely find the same back east or where ever you cross into Canada.
In Canada we have these big box stores called Canadian Tire they carry everything from car parts, TV's home repair supplies and blenders, they also "usually" have a good assortment of paper maps of the Canadian provinces and some USA States.
Also you can find Canadian Hwy / road maps on Amazon.com ( com = USA) I just looked they have tons of them.
As others have said Milepost doesn't have a very good map showing much detail other than the straightest routes north to Alaska from the USA. Yes it does show some other Hwys up here but not all of them. Looking at the map that came with my last edition of Milepost, that map doesn't cover 1/2 the hwys around here, it is just a basic map, with not much for detail.
I even have a road atlas put out my McNally Rand and it is even missing a lot of roads up here in BC anyways.
Try Amazon.com, order provincial maps for where you will be traveling, I just looked they carry a lot of Canadian Maps.
Canadian maps on USA Amazon Soup.
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