Originally boasting 19 covered bridges, six remain today in Madison County Iowa. All are listed on the National Register of Historic Places. The bridges were covered by order of the County Board of Supervisors to help preserve the large flooring timbers, which were more expensive to replace than the lumber used to cover the bridge sides and roof. Usually, the bridges were named for the resident who lived closest. "The Bridges of Madison County" was made on location in Madison County, Iowa, and several covered bridges and various buildings and locations were used in the movie.