A method of generating data representative of a geographical network (such as a road network) is disclosed, comprising steps of selecting from a database (2) data relating to an extended junction (formed from at least one node at least one edge) and outputting the selected data. The method address problems in existing devices relating to the selection of appropriate data, and finds particular application in the field of mobile devices and the like. Apparatus for generating data representative of a geographical network and a method of providing a graphical schematic of a location are also disclosed.