The official site of Hardrock Hundred Mile Endurance Run is chicagomarathon.com . It was held in 11 August – 28 August . 1963 is when Hardrock Hundred Mile Endurance Run was established  . 136 from 25 nations competed in Hardrock Hundred Mile Endurance Run . 17 teams competed in Hardrock Hundred Mile Endurance Run . The venue for Hardrock Hundred Mile Endurance Run was Riocentro – Pavilion 6
136 contenders from 25 nations