Map data is managed by being divided into a geometric information data list of pieces of geometric information or a phase information data list of pieces of phase information, an attribute information data list of pieces of attribute information, and a relation information data list of pieces of relation information each indicating a relation between the geometric information or the phase information and the attribute information. The pieces of attribute information in the attribute information data list are arranged in the order corresponding to the pieces of geometric information or phase information which are feature information, and the pieces of relation information are arranged in the order corresponding to the pieces of geometric information or phase information which are feature information.