The Pottawattamie County Sub Courthouse was built in 1885 in Avoca, Pottawattamie County, Iowa. It was Iowa's only branch county courthouse, it is in the eastern portion of a wide county, the county seat in Council Bluffs is located at the western edge. The building was refurbished in 1998; as of 2011, the building was used to house several county offices and the local historical society.