Of the five ‘Classic’ races run in Britain – namely, the 2,000 Guineas, 1,000 Guineas, Derby, Oaks and St. Leger – the 1,000 Guineas and the Oaks are restricted to three-year-old thoroughbred fillies, but the other three are open to three-year-old thoroughbred colts and fillies. Nowadays, the Derby is rarely contested by fillies; the last filly to run in the race was Cape Verdi, trained by Saeed bin Suroor, who started favourite after winning the 1,000 Guineas in 1998, but could finish only ninth of the 15 runners. Nevertheless, since the Derby was inaugurated in 1780, a total of six fillies have won; the most recent of them was Fifinella who, in 1916, won a ‘substitute’ Derby run at Newmarket and, just for good measure, won the so-called ‘New Oaks’, over the same course and distance, two days later.
Not to be confused with its adjectival form, when used as a noun in horse racing circles, ‘Classic’ – often, but not always, capitalised – has a highly specific meaning. In Britain, the term refers to any of the five principal races for three-year-old horses, which are, in chronological order, the 2,000 Guineas, the 1,000 Guineas, the Oaks, the Derby and the St. Leger. The 2,000 Guineas, the Derby and the St. Leger are open to three-year-old thoroughbred colts and fillies, but the 1,000 Guineas and the Oaks are restricted to three-year-old thoroughbred fillies. Collectively, the former three races are sometimes referred to as the ‘Triple Crown’; the last horse to win all three was Nijinsky in 1970. The term ‘Classic’ can also be used to describe equivalent races in countries other than Britain, such as the Prix du Jockey Club, also known as the French Derby.