Average Gradient Formula Geography

Tennis has four Grand Slam tournaments: the Australian Open, French Open, Wimbledon and US Open.

The Australian Open takes place at Melbourne Park in Melbourne and began in 1905. The French Open started in 1925 and is played at the Roland Garros in Paris. Wimbledon, which dates to 1877, is the oldest major and is held at the All England Club in London. The US Open began in 1968 and takes place at the USTA Billie Jean King National Tennis Center in New York City.

Who has won the most Grand Slam titles? Let's take a look at the all-time leaders for men's and women's singles.

MEN'S GRAND SLAM SINGLES TITLES

1. Novak Djokovic, 24

2. Rafael Nadal, 22

3. Roger Federer, 20

4. Pete Sampras, 14

5. Roy Emerson, 12

WOMEN'S GRAND SLAM SINGLES TITLES

1. Margaret Court, 24

2. Serena Williams, 23

3. Steffi Graf, 22

4. Helen Wills Moody, 19

5. Chris Evert, 18 (TIE)

5. Martina Navratilova, 18 (TIE)

Be sure to check out ESPN's tennis coverage, which features breaking news, analysis, features, rankings, Grand Slam title winners and more.