[2] The Mosby Creek Bridge was built in 1920 for a cost of $4125 (US$62,738 in 2025) by Walter and Miller Sorensen.

He settled east of present-day Cottage Grove near the current site of the bridge on a 1,600 acres (650 ha) land claim.

[4] Unique design elements of the Mosby Creek Bridge include semi-circular portal arches (the entrances to the bridge), ribbon openings at the roofline, and board-and-batten siding, as well as modifications to the basic Howe truss design.

[3][6] In 1979, the bridge was added to the National Register of Historic Places.

[2] The Mosby Creek Bridge receives regular maintenance from the county.