The design, dimensioning and cost estimation of a district heating network poses many challenges. Especially for large networks, producing a network layout manually is complex and time-consuming. Custom-made spreadsheets allow automated hydraulic calculations and pipe selection, but can be error-prone if not properly used and are not suitable for large networks. The network deployment cost estimation is also typically calculated with yet other spreadsheets. In short, the different design aspects typically require different software tools and the process is usually not well-integrated. This makes the design process expensive and time-consuming. This paper discusses solutions to the challenges stated above provided by an automated, geographical information system (GIS) based planning tool. The tool has been developed as a plug-in to a GIS tool and includes optimized and automated network routing algorithms, including all aspects of a district heating network dimensioning as required for a feasibility study. A neighbourhood of Nijmegen used as a case study to demonstrate the tool, showing the effect of different design parameters such as network pressure level and substation size on total network dimensions, cost and performance. Several cases for future heat demand scenarios were simulated to analyze their impact on network cost and performance. (C) 2019 Elsevier Ltd. All rights reserved.