When you go to the Grand Canyon, and talk to people they have gone down and hiked it, you will always hear about those that did it in one day or even hiked rim to rim to rim. There are people that hike rim to rim EVERY year.

In hindsight, I wish we had done it differently. We started at 5am and finished at 5:15pm. We hiked at about 3.5 miles in every hour. No time for pictures, very few breaks. If you want to get out in sunlight, you have to keep moving. It's a standing joke at REI that the people who do it in a day are moving constantly and looking at the heels of someones shoes all day.

In hindsight, I would have preferred to hike down to Phantom Ranch, stayed over, taken our time, and then hiked out the next day.

So think about this as you do it. What is the big wooha about doing it in one day? I honestly don't know.