Of the five British Classics, two of them – that is, the 1,000 Guineas and the Oaks – are restricted to three-year-old thoroughbred fillies, so it is impossible for a colt to win more than three. That said, a total of fifteen colts have won the 2,000 Guineas, the Derby and the St. Leger, a.k.a. the ‘Triple Crown’, while nine fillies have won the 1,000 Guineas, the Oaks and the St. Leger, a.k.a. the ‘Fillies’ Triple Crown’. Remarkably, though, two of those fillies not only ran in, but won, the 2,000 Guineas, taking their tally to four English Classics.
In 1868, Formosa, trained by Henry Woolcott, dead-heated with the colt Moslem in the 2,000 Guineas, before easily winning the 1,000 Guineas, over the same course and distance, two days later. She subsequently won the Oaks, by 10 lengths and, despite being beaten, twice, at Royal Ascot, was sent off joint-favourite for the St. Leger at Doncaster, which she duly won by 2 lengths under just hands-and-heels riding.
In 1902, Sceptre, owned and trained by Robert Sievier, started her three-year-old by being narrowly beaten, under 6st 7lb, in the Lincolnshire Handicap, but went on to win the 2,000 Guineas and the 1,000 Guineas, again within two days. She was arguably unlucky not to win the Derby, finishing fourth after missing three days’ work with a bruised foot, but returned to winning ways when hacking up in the Oaks two days later. Subsequently, she ran in the Grand Prix de Paris, twice at Royal Ascot and twice at Glorious Goodwood but, come the autumn, still managed to beat Rising Glass, who had finished second in the Derby, in the St. Leger. In so doing, she became the first and, so far, only horse to win four British Classics outright.