An area indicated on the zoning map as a public park, recreation area, public school site, cemetery or other similar open space, shall not be used for any other purpose than that designated; and when the use of the area is discontinued, it shall automatically be zoned to the most restricted adjoining district until appropriate zoning is authorized by the city council within three (3) months after the date of application filed for rezoning. (Ord. 233, 7-3-1978)