According to Ordnance Survey (OS), the Integrated Transport Network (ITN) layer is the definitive, most accurate and up-to-date geographic reference for Great Britain’s road structure representing all navigable roads, from motorways to alleyways. The core of this dissertation lies in the fact that the ITN holds a detailed road network concerning X and Y coordinates but this contains no height information. The target of this dissertation is to develop an algorithm capable to attach height information to sample areas which could then be used to extract useful information concerning road network height characteristics, such as gradient and altitude. The aim is to demonstrate the usefulness of this enriched data model. Visualisation tools were used and network analysis was performed to demonstrate how the 3D ITN layer can be proved beneficial for a variety of decision-making applications.