Many already know this, but the advice I always give for the Grand Canyon itself is to make sure to take one of the trails 'below the rim' as you will have missed out on a completely different set of sights, sounds and smells, than if you merely go to the edge and look over.

Even if its just a few hundred feet down, please do it. Just plan to spend twice as long coming out than going in (15 minutes down = 30 minutes up).

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