 Denver used to be a major trading center for beef and livestock when ranchers would drive ( or later transport ) cattle to the Denver Union Stockyards for sale . As a celebration of that history , for more than a century Denver has hosted the annual National Western Stock Show , attracting as many as 10 @,@ 000 animals and 700 @,@ 000 attendees . The show is held every January at the National Western Complex northeast of downtown . 
