Analysis of traffic information is an essential part of creating and operating any traffic information system that provides its customers with accurate and timely data about the traffic status of a road network. As the amount of data generated by these systems is vast, there is an urgent need to provide system developers, traffic engineers and analysts with a tool that would allow them to easily visualize and observe collected traffic data. This thesis presents such an information system which is used for traffic data analysis and visualization at TomTom International B.V. Common techniques for traffic data analysis are summarized and an outline of the complete architecture and implementation of the system is provided. The proposed architecture is based on the service oriented architecture paradigm, which in combination with stateless services resulted in a highly extensible and scalable system. The implemented system has been deployed into the production environment and is intensively used for daily operations to analyze the TomTom High Definition traffic data chain. It has proven itself to be an effective tool and has helped to improve the overall quality of the data.