Hamlin is an unincorporated community in Audubon County, Iowa, United States. History Hamlin was laid out in 1872. It was named for Nathaniel Hamlin, a pioneer settler. Hamlin's population was 14, in 1902. See also T-Bone Trail References Unincorporated communities in Audubon County, Iowa 1872 establishments in Iowa Populated places established in 1872 Unincorporated communities in Iowa