The Triple Crown is one of the most prestigious and celebrated achievements in North American sports. In American horse racing, the Triple Crown is attributed to any three-year-old thoroughbred who is able to accomplish the feat of winning the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes in the same year.

The trifecta is one of the most rare achievements in sports. Only 13 horses have won the Triple Crown since 1875, the first year in which all three races were held at the same time.

The Kentucky Derby takes place at Churchill Downs on the first Saturday in May each year. It is followed by the Preakness Stakes, which takes place two weeks later at Pimlico Race Course in Baltimore on the third Saturday in May. The Belmont Stakes, the last of the three races, is held in New York City three weeks after the Preakness Stakes.

Here’s a look at every winner of the Triple Crown in horse racing.

It took 44 years before the first Triple Crown winner emerged: Sir Barton won all three races in 1919.

Eleven years later, Gallant Fox managed to gallop in Sir Barton’s hoof steps with a Triple Crown in 1930. For the next 18 years, a horse managed to accomplish the feat every two and a half years. Citation became the eight Triple Crown winner in 1948. However, a 25-year wait for the next Triple Crown winner brought back some of the prestige, anticipation and rarity to the honor.

Secretariat captured a Triple Crown in 1973 to become the first of three Triple Crown winners in the 1970s. Seattle Slew and Affirmed accomplished the feat in back-to-back years in 1977 and 1978, but that was followed by nearly four decades without another winner. The 37-year dry spell was ended with Triple Crown victories by American Pharoah in 2015 and Justify in 2018.

Justify, the last Triple Crown winner, became the first horse to win the Kentucky Derby despite not participating races as a two-year-old horse. Still, Justify’s Triple Crown has been questioned after it was revealed that the horse had tested positive for scopolamine, an anti-nausea medications that is considered to be a performance-enhancing drug. After years of litigation, Churchill Downs announced they do not plan to rescind Justify’s achievement, but noted that there were new rules in place to prevent a similar scenario in the future.