A golf course consists of a series of holes, each consisting of a teeing area, fairway, rough an other hazards, and the green with the pin and cup. Because a round of golf consists of playing 18 holes, most golf courses have this number of holes. Some however only have nine holes and the course is played twice per round, while others have 27 or 36 and choose two groups of nine holes at a time for novelty and maintenance reasons. Many older golf courses, often coastal, are golf links, of a different style to others. For other than municipal courses, there is usually a golf club based at each golf course.