On this day in 1977, racehorse Red Rum wins a historic third Grand National championship at Aintree Racecourse in Liverpool, England, after taking home victory in 1973 and 1974 and finishing second in 1975 and 1976. Red Rum remains the most successful horse in the history of the Grand National, which is considered by many to be the world’s toughest steeplechase race.

The first Grand National at Aintree was run on February 26, 1839. Today, the course is 4 miles 856 yards and contains 30 fences. The 1929 Grand National featured the largest number of starting horses, 66, while the 1883 event featured the smallest number, 10. The largest number of horses to finish the event was 23 in 1984, while the smallest number was just two in 1928. The Grand National is the biggest betting horse race in Britain, as well as the one most popular with people who typically don’t follow the sport.

Red Rum, a bay gelding, was foaled on May 3, 1963, at the Rossennara Stud in Kells, County Kilkenny, Ireland. His moniker was derived from the last three letters of the names of his dam and sire, Mared and Quorum. Early in his racing career, it was discovered Red Rum had a debilitating bone disease; however, trainer Ginger McCain, who bought the horse for Noel Le Mare, trained him on the sand and in the sea water at Southport, Merseyside, which apparently cured Red Rum of his foot problem. In 1973, Red Rum, ridden by jockey Brian Fletcher, won his first Grand National when he beat Crisp with a record time of 9 minutes 1.9 seconds, a number that would stand for 16 years. Fletcher was replaced with Tommy Stack at the 1976 Grand National and on April 2, 1977, Stack rode Red Rum to his record-setting third Grand National victory. Before the race, there was speculation that 12-year-old Red Rum was too old to compete. Of the 42 horses that started the race, only nine finished the grueling course. Two horses had to be put down after falling.

Red Rum was scheduled to run in the 1978 Grand National, but on the morning of the race it was determined he had a hairline fracture. The horse, age 13, was then retired from racing; however, his fame in Britain continued to grow and he made numerous publicity appearances. In October 1995, Red Rum, then 30 and in failing health, was put down. The champion horse was buried near the winning post at the Aintree track.