Urban nature reserves are increasingly popular for recreational activities but who uses them, for what activities, and when and where do visitors go? Volunteered geographic information has only recently started to be used by managers to examine patterns of trail use in reserves. As yet, little is known about the benefits and limitations of this type of data. Therefore, we compared how mountain bikers, runners and walkers use popular reserves (Daisy Hill Conservation Park, Venman Bushland National Park and Bayview Conservation Area) close to Brisbane, Australia, based on extracted route data from the fitness tracking application MapMyFitness. Routes for all three activity types were displayed and analysed using ArcGIS. Mountain biking was more popular (49% of the 948 routes), than walking (27%) or running (24%) across the three reserves. Route data was effective at predicting the relative popularity of specific trails with significant linear regressions when compared with fixed-point trail counts (R2 = 0.681). Bikers went further, used a greater range of trail combinations and used more reserves per trip than the other two activities. Weekends were popular for all three activities, but more so for biking (57%), than walking (44%), or running (43%). The results highlight how volunteered geographic information complements other trail data allowing urban planners and managers to better assess visitor movements in reserves. A number of specific management challenges were identified, such as bikers using more areas within and across the reserves, and in some cases, the use of private land and unauthorised access points.