hwy 78 between El Centro,CA and I-10

Came that way Sunday from Blythe and cut off above Glamis to get to Yuma. Basically, like the rest said but when getting closer to Blythe you will have some stop signs.

If you don't mind a two lane road with occasional narrow shoulders and drop off into deep rock filled gulleys it's a good way to go. You'll likely see lots of RVs along the way. And some beautiful huge sand dunes soon after leaving the El Centro area. We run it all the time but just for variety will occasionally route thru Yuma.

I have taken highway 78 from El Centro to Blyth and did not find it remarkable for any steep hills, or other reasons.

You will find less expensive gas in Arizona, and if you will be going all the way to Phoenix, then highway 85 north to Goodyear is another option that works well. Highway 95 to Quartzsite is also a great road.

Several times I have taken highway 8 further east to a cut off going north through Maricopa, via highways 84 and 347 when my destination was Gilbert AZ. SO I guess it all depends on your destination. When I wanted to see Slab City, I took highway 111 to Niland, and slab city is just east of there, an old Army base, popular with dry campers in the winter.

Have fun!

Fred.