In this chapter, we present a novel systematic way of building a web-based geographic information system (GIS) running on cloud services. The proposed architecture aims to provide a design pattern for building a cloud-based GIS using simple and readily available low-cost tools with great overall system efficiency. The result of running the GIS using this paradigm is arguably reliable and available at low cost and with some platform independence. It has required significantly less time and effort to deploy when compared with standard cloud development. We present a case study based on road accidents using Microsoft Windows Azure and Amazon Web Services. In this case study, a GIS was created that helped in improvements of road conditions by identifying road accident hot spots in real time and 142on the real map. Later, authorities can use this information to implement preventive measures to reduce road accidents. This GIS can be implemented for any town, city, county, or region in the world as long as its satellite maps are available on Microsoft Bing Maps.