Question: coming from St George, is it better to approach Valley of Fire via 169 and then head to Vegas on Valley of Fire Hwy, or just go in and out Valley of Fire Hwy?
Thanks for tips!
Depends on how much time you have. Entering V of F from the Northwest off I-15 and 169 and returning to I-15 by the same route will get you to LV faster, but that portion of I-15 is not scenic and requires you to cross all of LV if you're bound for the airport. Alternatively, after entering V of F from I-15, continuing to Las Vegas via NV 167 and NV 147 or (better) NV 564 and I-515 via Henderson, NV is MUCH prettier but probably at least two hours longer. More if you stop to shoot the scenery. A superb (and traffic-free) bit of asphalt, it would be gorgeous in the late afternoon.