Located in Mason City, this through girder bridge crosses 1st Street Southwest near Monroe Avenue.
Reportedly built in 1910, the bridge consists of a single through girder set onto concrete substructures. Writing on the bridge implies this bridge was supposed to go to Bridge #501 1/2, which is located in Missouri Valley, Iowa.
It is possible that this bridge was moved here instead of there, due to that bridge needing a bigger span. In that case, it is unknown where this bridge may have come from.
Overall, the bridge appears to be in good condition, with little deterioration.
The author has ranked this bridge as being locally significant, due to the common design.
The photo above is an overview.