Uncovering round-trip patterns in bicycle sharing: Differences in short-distance travels from home-based, work-based, and river-based neighborhoods

Analyzing neighborhood-level bicycle usage is pivotal for developing effective policies and promoting bicycle-friendly initiatives. Although data from bicycle sharing systems (BSS) have become increasingly accessible, round-trip travel remains underexamined compared to one-way or last-mile commuting trips. This study addresses that gap by investigating round-trip usage in Seoul's BSS, which adopts a low-cost, flat-rate fare structure that encourages short-distance trips. Using a Bayesian Gaussian Mixture Model (BGMM) on 347,252 GPS trajectories from round trips, we identified visited points of interest (POIs). We then analyzed travel characteristics and POI visitation patterns across three neighborhood contexts: home-based, work-based, and river-based. Round trips accounted for 11 % of BSS usage but showed longer durations (40.35 min vs. 22.47 for one-way trips) and distinct time peaks around midday and evening. POI visit patterns varied by context: 73.8 % of round trips in river-based areas led to open spaces, while home-based neighborhoods saw more visits to daily life services and education. Work-based areas had higher visitation to food-and-beverage and business facilities. A micro-scale cluster analysis revealed more dispersed POIs near river-based stations, and more concentrated ones near home- and work-based stations. These findings underscore the versatility of shared bicycles as a standalone mode of transportation beyond commuting. By clarifying how visit patterns vary by neighborhood type, this study provides actionable insights for BSS operations and urban planning, including station placement and rebalancing strategies tailored to local travel needs.