11 from 2 nations competed in US Open . The no. of events in sport was 18 . The sport has the official site chicagomarathon.com . US Open was founded on 1884; 135 years ago (1884) . Georgia Dome,New York City, New York,,United States were the venues of US Open . 24 (from 5 confederations) teams participated in US Open
There were 24 games in US Open