Wikipedia
WMSTR
WMSTR, or the Western Minnesota Steam Threshers Reunion, is an annual, non-profit "steam meet" held in the small town of Rollag, Minnesota. It takes place over the weekend of the US Labor Day holiday (first Monday in September), and draws around 80,000 visitors during the four days of the event.
Beginning in 1954, the reunion has grown from a few farmers threshing grain, as their fathers had, to one of the largest steam venues in the nation. Antique and steam tractors and automobiles are featured.