Riverside is a city in rural Washington County, Iowa, United States, along the English River on Iowa Highway 22. It is part of the Iowa City, Iowa Metropolitan Statistical Area. The population was 928 at the 2000 census. It is part of the Highland Community School District.
Riverside proclaimed itself the future birthplace of Captain James T. Kirk, a fictional character from the television series Star Trek, with the agreement of Gene Roddenberry.
The settlement of Riverside was established in 1872 and incorporated in 1882. The name, suggested by a Dr. Mott, is probably a reference to the townsite's location on the English River.