The sport has the official site chicagomarathon.com . It was held in 11 August – 28 August . Pontal, Rio de Janeiro,54.5 km (33.9 mi) were the venues of US Open . 8 events were there in US Open . 1884; 135 years ago (1884) is when US Open was established 
The sporting event US Open took place on 10 August 2016