There is an old golfing legend that claims 18 holes were chosen because of a suggestion from a St Andrews old-timer who said that it took exactly 18 shots to finish a fifth of scotch, one shot per hole.
However for early golf courses the number of holes used to vary widely, Leith Links only had 5 holes in 1744, Blackheath had 7, Bruntsfield expanded its number to 6 in 1818, Prestwick was built in 1851 with 12, Musselburgh had 9 in the late 1800’s and Montrose had got to 25 holes in 1866!
The original course at St. Andrews (dating back to the 15th century!) consisted of 11 holes played along a narrow strip of land next to the sea. The land was so narrow that golfers played to the same holes on the way out and coming in, so each was played twice for a total of 22 holes.
In 1764, the Society of St Andrews Golfers, later to become the Royal and Ancient Golf Club, decided that some of the holes were too short and combined them, so the course made the switch to 9 holes (each played twice).
In 1858, the Royal & Ancient Golf Club of St. Andrews, issued a new rule for its members stating that one round of links, or 18 holes, constituted an official match. In 1867 Carnoustie extended their ten hole to eighteen and the other courses pretty much followed suit after that, and by the 1870s, 18 holes was the standard.
