Hardbound. Computer-based transportation applications and databases have been a fact of life for several decades. Transportation information, however, has often not been accessible in a user-friendly manner, and integrating data from diverse sources has too often been a challenge in itself. Geographic Information Systems (GIS) have revolutionized spatial planning and decision making by using the spatial dimension of the depicted world as a common thread according to which all information can be referenced. The application of GIS to transportation research (GIS-T) is quickly becoming a mature...