Kogan says that it's a 1300 mile drive. Even at 70 mph, thats still 18 and a half hours of driving. I don't think that's even legal, let alone practical. The only way I see we could manage that is if we had several drivers in each car and we had them switch off or something, which would still be an utter bitch. I think we're going to have to stop and sleep at least once. that leaves us with a little bit more than 9 hours a day, which is still painful but is a lot more doable.
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If we do stop to sleep, do we actually have to pay for rooms, or is it legal to set up tents in empty parking lots and such? Or just sleep in the cars? It's not very comfortable, but if legal it would save on money.
Having done this sort of thing before...
I do not believe there is any laws reguarding POVs, but following the laws for truck driving is generally good practice. 3 hour "bursts" with 30-45 minutes in between for about 3-4 times works very well with long cross-country driving. You can alternate drivers like that and go non-stop across half the country without any significant fatigue, though it really depends on the driver. The important thing is not to drive while tired, and to keep your focus by taking breaks. 4 hours per break is generally recognized as the ideal for concentration. Fortunately rest stops are generally more common than that
The fun part is to see the petrified chief's droppings along the way (what my family calls all the little sites which claim historical significance but you won't find in any history book ever. Usually they are at rest stops.)
I-70 isn't the only potential route. The exact route should depend on if we need to pick someone up along the way or not.
US 6 IS I-70.
Also, the more people crammed into one vehicle, the more that can split the cost of gas and the more who can be used to ensure it's a safe drive, but also the less space available. It's a $540 gas bill I believe, more or less depending on MPG and price of gas at each gas station. At $200 flight per person (which I can't find), that means it's more economical for 3 people to go in 1 car than 3 in airplanes.