The Grand Canyon had been a bit of a letdown for me on my last visit. We had spent a week visiting parks in the southwest including Mesa Verde, Bryce Canyon, Zion National Park, Canyonlands, and the north rim of the Grand Canyon. Bryce and Zion were my favorites by far. This time, however, instead of doing a moderate day hike down and back from the north rim, I was making the ultrarunner pilgrimage from the south rim to the north rim and back. Experiencing the Grand Canyon from one side to the other was incredibly awesome and completely worth it. Highly recommended, not that it needs it given the vast numbers of runners and hikers we encountered. That was actually the biggest surprise to me, the number of runners and day hikers all along the route. I had expected large numbers of people near the trailheads but was shocked by what seemed like multiple busloads of people in the middle of Bright Angel Canyon, ten or so miles from either trailhead.
We parked about 1/2 mile from the South Kaibab trailhead a little after 6am and jogged the 1/2 mile to the trailhead to start the run. I had read a lot of reports suggesting a 4am start from this trailhead in order to leave before the first mule train. I highly recommend starting at 6am or first light, whichever is later since the first mule train reached the bottom before us with this timing. We did meet a mule train coming towards us just after we crossed the bridge at the bottom but that did not cause much of a delay. The second reason for leaving at daylight is that I would rather finish the final climb at the end of the day with a headlamp (which I did) than run down the trail by headlamp. For some reason, I am thinking maybe the color of the dirt, depth perception was very difficult on this trail despite the bright headlamp I used. Kudos to everyone who goes down by headlamp, but given the steepness and the number of logs/steps built into the trail I would think going down in the dark would really slow you down a lot whereas I was going to be moving slowly climbing back up to the rim at the end of the day regardless.
I lucked out to tag along with Shad and a group of great runners from Las Vegas which meant the logistics were all taken care of for me. However, if you are looking for logistical help, Andrew Skurka's website has lots of great information. The Garmin recording of my run is here.