An electronic device merges a plurality of maps, or area description files (ADFs), by representing relationships among ADFs in an undirected graph, with vertices representing maps and edges representing transformations between maps. As the electronic device generates new ADFs, the electronic device merges each new ADF to a stored collection of ADFs by adding each new ADF as a vertex and transformations between the new ADF and the collection of ADFs as edges in the undirected graph. In this way, the map merger can use the undirected graph to more accurately represent the relations between any two maps, allowing more efficient merger of new maps to a previously stored collection of maps, and allowing for the development of more flexible and efficient algorithms for manipulating the merged maps.