It depends on what you want to do and what time of year you plan to visit. Stay in one of the park hotels - reserve as far in advance as possible. Same for rafting or mule trips. Doubly important if it's during high season. If you just want to stay nearby, do some basic tours, or hike the trails on your own, you can easily just show up in low season. But you should probably do some advanced planning if it's during high season because everything that takes a reservation will be booked. You can always hike on your own but you might not have a place to sleep.
Do some research on the internet, YouTube, Google Map...This certainly can help plan ahead
You dont have to make the trip in advance...you just go! Thats pretty much what I did!
It is about 450km from Las Vegas. Great transit
For camping/lodging or a day trip?
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