Rodeos are an important part of the culture in Eastern Oregon, and Union's annual rodeo and livestock show is the longest continually running rodeo in the Northwest. 4-H and FFA participants get a chance to show and sell their livestock. There are always great food and souvenir vendors, as well as a carnival. On top of all this, there is a professional rodeo, with bull and bronc riding, horse racing, and much more. A weeks worth of events not to be missed. June 10, 2016. The Eastern Oregon Livestock Show Grounds, 760 E. Delta, Union.