In Britain, the term ‘Classic’ is used to describe any one of five oldest and most important races in the Flat racing calendar. Those races are, in chronological order, the 2,000 Guineas, the 1,000 Guineas, the Oaks, the Derby and the St. Leger. They became known as ‘Classics’ in 1815, shortly after the inaugural running of the 1,000 Guineas.
The 2,000 Guineas and the 1,000 Guineas are both run over a mile at Newmarket in late April or early May, but the 2,000 Guineas is open to three-year-old colts and fillies, while the 1,000 Guineas is restricted to three-year-old fillies. Similarly, the Oaks and the Derby are both run over a mile and a half at Epsom in June, with the Oaks restricted to three-year-old fillies and the Derby open to three-year-old colts and fillies. The St. Leger, run over a mile and three-quarters at Doncaster in September, is also open to three-year-olds of both sexes although, as is the case with the 2,000 Guineas and the Derby, geldings are excluded.
The 2,000 Guineas, Derby and St. Leger constitute the so-called ‘English Triple Crown’ in horse racing, last won by Nijinsky in 1970. By the same token, the 1,000 Guineas, Oaks and St. Leger consitute the so-called ‘Fillies’ Triple Crown’, last won by Oh So Sharp in 1985.