1. A method of modifying 2.5D GIS data for a 2D GIS system, the method comprising: displaying 3D graphic indicia produced by a 3D rendering engine on a display device, the graphic indicia being displayed by the 2D GIS system that receives the 3D graphic indicia from the 3D rendering engine, the graphic indicia being displayed in a geospatial manner as a function of 2.5D GIS data in a GIS database associated with the 2D GIS system; and modifying the 2.5D GIS data in the GIS database using the 3D graphic indicia displayed on the display device, including mapping user selections relating to the 3D graphic indicia to 2D geo-location coordinates for the 2D GIS system and modifying the 2.5D GIS data by the 2D GIS system based on the 2D geo-location coordinates.