All-Time North American Best 100-km Performances UltraRunning Magazine 11/24/2013 UltraRunning Magazine 11/24/2013 421 Below is a listing of the all-time top performances at 100-km for North American residents. Thanks to Franco Anichini for the compilation of most of this data. Updated April 23, 2012 FacebookTwitterEmail UltraRunning Magazine More from UltraRunning Ultrarunning on a Budget Gary Cantrell on Rules Review: La Sportiva Motion Shirt and Rapid Shorts One Plus One Equals Three 2016 UltraRunners of the Year Finding Grit for the Grind