On April 18, 1980, a marathon runner in a long-distance road race took a wrong turn during the event and continued for miles off the marked course before finishing. The incident highlighted how easily a single navigational error could affect results in mass-participation races, and it exposed weaknesses in course marshaling and signage that organizers of that era were still addressing. Marathon courses rely on a combination of pre-race markings, volunteer marshals, police escorts and the presence of other runners to guide participants. In 1980, many races were expanding rapidly in size amid growing public interest in distance running, but race-management practices and resources varied widely. In some events, particularly smaller or newly established races, marshaling gaps or unclear directional signs could leave runners uncertain at turns—especially where courses passed through busy intersections or areas with multiple possible routes. When a runner missed a turn and continued on an unintended stretch of road, the practical consequences included a longer actual distance run, a finish time that did not reflect the official course, and potential effects on placing for that runner and others. Race officials historically have dealt with such situations in different ways depending on the circumstances: disqualifying the runner for not completing the certified course, adjusting results if timing evidence and course monitoring allow, or, in some informal events, accepting the finish but noting the deviation. The specific resolution for the April 18, 1980 incident is not universally documented in public records, and practices varied by event organizer and governing body at the time. Incidents like this prompted incremental changes in race operations over subsequent decades. Organizers increasingly standardized pre-race course inspections, increased the number and visibility of directional signs, assigned more volunteer marshals at critical junctions, and developed procedures for handling course deviations. The advent of widespread electronic timing and later GPS tracking added tools for race directors to detect and adjudicate off-course performances, though such technologies were not available in 1980. From a historical perspective, wrong-turns in endurance events are a recurring issue rather than a novel phenomenon. They illustrate the interplay between human factors—fatigue, concentration lapses, following the wrong crowd—and event infrastructure. While prominent, well-resourced marathons typically had better safeguards even in 1980, smaller races and those undergoing rapid growth were more vulnerable to course-control lapses. Reporting from the period and retrospective accounts note several instances across the late 1970s and early 1980s where course confusion affected results, contributing to evolving best practices. Where available, contemporaneous race bulletins, local newspaper accounts and organizational records are the primary sources for documenting individual incidents and decisions. Because formal documentation for every local race was not always preserved or published, some specific resolutions remain unclear unless preserved in archives or personal records. The April 18, 1980 wrong-turn episode thus serves as an example of how logistical details can materially influence athletic competitions. It underscores why consistent course marking and marshal placement became standard priorities for race directors in the years that followed, and why modern races emphasize pre-race briefings, visible signage and volunteer training to reduce the likelihood of similar errors.