The Portal transportation data archive (http://portal.its.pdx.edu/) was begun in June 2004 in collaboration with the Oregon Department of Transportation, with a single data source: freeway loop detector data. In 10 years, Portal has grown to contain approximately 3 TB of transportation-related data from a wide variety of systems and sources, including freeway data, arterial signal data, travel times from Bluetooth detection systems, transit data, and bicycle count data. Over its 10-year existence, Portal has expanded both in the type of data that it receives and in the geographic regions from which it gets data. This paper discusses the evolution of Portal. The paper describes the new data, new regions, and new systems that have been added and how those changes have affected the archive. The paper concludes with a section on the uses of Portal that provides several examples of how Portal data have been used by regional partners, with a focus on measuring the performance of the multimodal transportation system, but also including educational elements and research
