The emergence of smart phones with embedded sensors has led to an explosion in the number of transport related research projects that leverage the widespread uptake of mobile devices. However, the process of collecting and managing travel-based sensor data in the field on a large-scale is difficult and resource-intensive. The process of obtaining a suitable dataset also provides an unnecessary distraction to researchers who are consequently unable to focus on the primary goals of their research such as gaining a better understanding of personal travel behaviors. In this paper we propose our vision for Citadel, an open community resource platform for collecting, managing and sharing archived travel sensor data to support transport research projects.