The American Triple Crown is one of the most prestigious accomplishments in horse racing. To win a Triple Crown, a 3-year-old thoroughbred must win the Kentucky Derby, the Preakness Stakes and the Belmont in the same year. These three internationally renowned races attract tough competitors and present varying track lengths, making winning the Triple Crown a difficult challenge.

Only 12 horses have made it to Triple Crown glory in the history of the sport. Although we saw a Triple Crown winner in 2015 when American Pharoah triumphed in all three jewels, the previous winner came 37 years earlier. Since 1948, there have been just four Triple Crown winners in total.

The first Triple Crown winner came in 1919 when Sir Barton ran away with the trio of stakes races. Ridden by Johnny Loftus and trained by H. Guy Bedwell, Sir Barton led the Kentucky Derby from start-to-finish. He did the same at the Preakness before also winning the Belmont Stakes shortly thereafter.

While Sir Barton was the first Triple Crown winner, Secretariat is the most famous. He holds the records for fastest time in each of the three races and a Disney movie was made in his name in 2010. Last year’s winner, American Pharaoh, might be the newest champ but he’ll be remembered for a long time. He also won the Breeders’ Cup Classic in the same year, making him the first horse to sweep all four major stakes races (Breeders’ Cup Classic was established in 1984).

One horse that will always be remembered for the wrong reasons is Alydar, who is the only thoroughbred to finish in second place in each of the three Triple Crown races in the same year. He lost out to Affirmed each and every time in 1978.

Jim Fitzsimmons is the only trainer to have won the Triple Crown with multiple horses (Gallant Fox and Omaha). As far as owners go, Calumet Farms and Belair Stud have each produced two winners: Whirlaway and Citation for Calumet and Gallant Fox and Omaha for Belair. Gallant Fox is the only Triple Crown winner to sire another (Omaha). As for as jockey fame goes, Eddie Arcaro is the only one to win the Triple Crown more than once, doing so with Calumet Farms' Whirlaway and Citation in 1941 and 1948.

Although there are just 12 Triple Crown winners so far, there could have been many more had they passed “The Test of the Champion.” That’s the nickname for the Belmont Stakes, which is the last and longest of the Triple Crown races. A total of 23 horses have won the first two legs of the Triple Crown (Kentucky Derby and Preakness) only to fail at the Belmont Stakes, the last being California Chrome in 2014.