A golf course is where the game of golf is usually played. It is made up of a series of 'holes', each consisting of certain key areas. A teeing ground is used to start playing the hole. A Fairway is the area between the tee and the green, where the grass is kept short for ball play. The green (or putting green) is a closely mowed area of grass surrounding the hole. It has a flagstick so the golfer can see the hole at longer distances. The hole itself has a diameter of 41⁄4 inches (108mm). Other areas of a golf course are called hazards. These include sand hazards and water hazards. Hazards are designed to make the game more challenging.