Drawing on a wide range of contemporary sources, Peter Lewis takes readers on a journey from 1764 to 1890 to discover why there are eighteen holes on a course. He reveals that early courses had varying numbers of holes and were judged by the quality of their turf, putting greens and hazards. He shows why, during the 1880s, as golf became more popular, the ideal number of holes was increasingly seen as being eighteen. In addition, he traces how St Andrews came to be perceived as the ‘metropolis of golf’ and why the Royal and Ancient Golf Club emerged as a governing body of the game. He draws multiple strands of evidence together to answer finally the questions of how and why eighteen holes became the ideal number for a golf course.