Soon after the county’s founding in 1853, the Fennimore County Agricultural Association would have organized and begun to scout sites for a fairground. Some sort of operation must have coalesced at Muskrat City until the courthouse moved to Agincourt. Muskrat City was established on lowland with ongoing flood issues; the town itself eventually faded from sight, with the exception of a store and post office, and that eventually closed during the Depression. All that remains today is one house and the foundation of the original bank.
I have some idea of the sequence of acquisition and evolution of the fairgrounds — the original quarter section became a wide triangle, reshaped by highway construction and a property swap — but only a vague notion of what buildings would have been built and in what order. Two things specific to the Fennimore situation: 1) the late 19th century Chautauqua Movement established a shed for their summer lecture circuit, and 2) after 1909, the Northwest Iowa Normal School developed a cooperative relationship and expanded their athletic facilities on the fairgrounds.
Its location across the river also made an opportunity for the new city trolley line to build a spur for seasonal service to the grounds — and a permanent pedestrian bridge for the normal school students. The Muskrat isn’t quite as deep as the trestle required here, but it would also have been produced by the seat-of-the-pants engineering.
Just imagine the alcohol-induced encounters between students and this bridge before A.D.A.