I am going to drive from Los Angeles and to Boise with a 10 month old puppy. I am planning on taking 2 days to do the drive because of her exercise and other needs. Would love route, food and puppy stop recommendations for both the outbound and the return. Thank you!
Bring plenty of newspapers. A long road trip could be so traumatic that it could cause her to regress and forget her house-training. I'd consider adding an extra day to your trip for her sake, and even that would be pushing the limits of what she can handle.
Driving from LA to Boise, once you get past Reno the terrain becomes more desolate and the gas/food/lodging becomes fewer and farther between. You'll need to take that into account as well.
The best route is to probably take I-5 to the Grapevine, then switch to Highway 99 through Bakersfield, Fresno and Sacramento. Then get on I-80 to Reno and Winnemucca, then switch to U.S. 95, which will take you north to I-84 and Boise. I'd recommend sleeping in Sacramento and Winnemucca.
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Do not drive through Nevada. To hot, no shade. Drive hwy 101 to Florence, Or; most of Oregon is pet friendly, especially the coastal area. From Florence take hwy 126 to Eugene etc. After you pass Bend, Or- there will be nothing but desert to Boise. (approx. 6hrs) I recommend a night on the beach. Most all hotels & all state parks are pet friendly. (unlike Cali) total drive time from Florence.... about 9hrs