Following an extensive research and documentation process, the Grinnell Historic Preservation Commission, the Grinnell Historic Neighborhood Association, and additional volunteers received good news in December of 2008: Their efforts to put the North Grinnell Historic District on the National Register of Historic Places had been successful. This area is made up of a 3.5 by 5-block rectangle bordered by Park Street, 6th Avenue, West Street, and 11th Avenue (Map 1).