The 1000 Guineas Stakes is a Group 1 flat horse race in Great Britain open to three-year-old fillies.
It can also serve as the opening leg of the Fillies' Triple Crown, followed by the Oaks and the St Leger, but the feat of winning all three is rarely attempted.
The two races were established by the Jockey Club under the direction of Sir Charles Bunbury, who had earlier co-founded the Derby.
They were named according to their original prize funds (a guinea amounted to 21 shillings, or £1.05).
The five leading events for this age group, characterised by increasing distances as the season progressed, were now referred to as "Classics".