Well... my 600K turned into a 480K, but it was a blast!
The Natchez Trace is an AMAZING road for cycling. Clean, low traffic, rest houses with water/bathrooms every 30-40 miles, and gorgeous smooth pavement.
The 600K ran from Nashville to Tupelo and back, all on the Trace. The turn-around was at Tupelo, and the overnight control was 40 mile back up in Tishomongo. The ride started at 6am, and it was in the upper 90's all day, with a strong headwind. We got to the Tishomongo exit on the way down, and although we could have (somewhat) easily made it another 40 miles to Tupelo, ate dinner and come back 40 miles to the overnight, we decided to just pull in, sleep, and have a good ride back. We knew it was gonna rain the next day, and amazingly, the wind was supposed to shift for a headwind in that direction too. We had 150 miles done, and considering we had strongly thought about not even attempting anything, we bailed. Went into the camp, slept, woke up to rain, puttered around waiting for it to let up, found out the rain wasn't stopping any time soon, so we just started riding back.
The rain let up about 50 miles later, and then the sun came out but the temps stayed cool for the rest of the ride. Even got some of the full moon after the sun set. Finished with just about 300 miles, 13,000 feet of elevation, 4 chicken sandwiches, 3 orders of fries, and two Juiced Rockstars!
So, my first 600K was a failure, but my first 480K was a success! (Not really, since we probably were outside of the time limits of an official 400K, but we had fun, and that's all that counts!!!)
For 3 days, I get to part of a thousand other journeys.