307.14  Official Iowa map.
  The department shall publish a map of the state of Iowa. At the request of a citizen of a particular city or town, the department shall add the city or town to the existing map of Iowa and identify the main road leading into the city or town if the city or town meets two or more of the following criteria:
  1.  Has a zip coded post office in the city or town.
  2.  Has a population of twenty-five or more.
  3.  Has a building on the national register of historic places in the city or town.
  4.  Has an association with a public recreation area managed by the department of natural resources in the city or town.
  5.  Has a high school, grade school, private school, church, or cemetery in the city or town.
  6.  Has a retail business in the city or town.
  7.  Has an annual festival or celebration.
91 Acts, ch 139, §1, 2