Justin Simoni, 60 days, 15 hours, 59 minutes (self-supported)
Simoni was the first, and currently only person to do the Colorado Centennials self-powered, and self-supported.
Rob Barlow, 71 days (supported)
Barlow is the first known person to do the Centennials self-powered, which is major in my book. Rob was supported by friends and family along the way, who followed him by car and joined him by foot. Barlow also traversed across mountains, and had gear (bike) waiting for him at disparate trailheads.