This paper illustrates how remote sensing technologies and geographic information systems (GIS) can be used to enhance modelling of urban greenway trail traffic and to draw inferences about the relationships between features of trail design and trail use. Measures of daily trail traffic come from a network of 30 infrared counters deployed over a 33-mile trail system in Indianapolis, Indiana. Among other results, the paper illustrates how Light Detection and Ranging (LIDAR) data obtained from an aircraft platform can be used to create three-dimensional surface models from which trail viewsheds can be measured and characterized. Regression modelling is used to correlate trail traffic with these viewshed characteristics and with other neighbourhood and control variables. The results provide empirical support for several design hypotheses. Other factors being equal, daily trail traffic is positively correlated with the openness of trail viewsheds, the greenness of trail viewsheds relative to surrounding neighbourhoods, and the diversity of land use within trail viewsheds. Trail traffic is inversely correlated with visual magnitude, a measure of the interconnectedness of a viewshed. Although theory suggests higher levels of pedestrian traffic may be associated with shorter block lengths, trail traffic is positively correlated with block length in trail neighbourhoods. Planners and designers can use this evidence base to enhance greenway planning and design.