Trails are essential transportation infrastructure supporting access to protected natural areas and providing recreation to hikers, runners, cyclists, equestrians, motorists, and many more worldwide. This research presents spatial studies intended to improve understanding of the environmental, managerial, and use-related factors that influence management of and physical and experiential conditions on long-distance hiking trails. The first study investigates a dataset from the Appalachian Trail (AT) to examine methods for using high resolution digital elevation models to measure terrain steepness near trails and along trails or potential trail routes. This analysis supports trail planning and assessment efforts because these terrain metrics strongly influence physical trail sustainability and are useful to evaluate the difficulty of travel along trails. The second study analyzes long-distance use patterns on the Pacific Crest Trail (PCT) as depicted by a computer model developed from a survey administered to long-distance hikers, trail counters, observations, and registers. In addition to describing use patterns, the process is intended to inform the selection of methods for visitor use monitoring in response to the complexity and level of controversy of management needs. The third study examines the spatial relationships between the PCT, a national scenic trail, and other congressionally designated land areas including wilderness, wild and scenic rivers, and national monuments and how this complexity is manifested in camping management strategies and impacts along the trail corridor. This analysis supports managing for the multiple congressional mandates across the PCT landscape and improves understanding and management of interagency transboundary travel on the trail. / Doctor of Philosophy / Trails are essential transportation infrastructure supporting access to protected natural areas and providing recreation to hikers, runners, cyclists, equestrians, motorists, and many more worldwide. This research presents spatial studies intended to improve understanding of the environmental, managerial, and use-related factors that influence management and physical and experiential conditions on long-distance hiking trails. The first study investigates a dataset from the Appalachian Trail (AT) to examine methods for using high resolution digital elevation models to measure terrain steepness near trails and along trails or potential trail routes to improve digital trail assessment and planning. The second study analyzes long-distance use patterns on the PCT as depicted by a computer model developed from a survey administered to long-distance hikers, trail counters, observations, and registers. The third study examines the complexity of managing transboundary long distance trails by quantifying the spatial relationships between the Pacific Crest Trail (PCT), a national scenic trail, and other congressionally designated land areas, and by reviewing camping impacts at high use locations on the trail corridor.