The five Classics form the bedrock of the British Flat racing season and are the benchmark on which careers and legends are based. The Derby (pictured), the Oaks, the 2,000 and 1,000 Guineas and the St. Leger identify the best thoroughbred three-year-old colts and fillies of their generation.
The Classic season begins with the 2,000 Guineas over Newmarket's Rowley Mile in May. First raced in 1809, it's a straight mile dash on turf for colts and fillies. The race is the first leg of the Triple Crown, alongside The Derby and the St. Leger, but the feat is rarely attempted.
The great Frankel, ridden by Tom Queally, was the runaway 2,000 Guineas winner in 2011 during his 14-win unbeaten career.
Saxon Warrior gave Irish trainer Aidan O'Brien a record ninth win in the race in 2018. The jockey was O'Brien's son Donnacha.
The 1,000 Guineas is the fillies-only equivalent, raced the following day over the same Rowley Mile course at Newmarket in Suffolk, England. Billesdon Brook, trained by Richard Hannon, became the highest-priced winner in the race's history when she won at 66-1 in 2018.
The 1,000 Guineas is the fillies-only equivalent, raced the following day over the same Rowley Mile course at Newmarket in Suffolk, England. O'Brien's Winter won in 2017.
The Oaks is the fillies' equivalent of The Derby, a mile-and-a-half test over the undulating Downs of Epsom, south of London. The Oaks comes on day one of the Derby Festival. Frankie Dettori rode Enable (pictured) to victory in a record time in 2017 to scupper O'Brien's quest to win all five Classics.
The Derby began in 1780, since when it has always been a highlight of the cultural and sporting calendar and attracts vast crowds of racegoers from every level of British society. Notable racing fan The Queen is a regular visitor.
The Epsom racecourse for The Oaks and The Derby features a long climb out of the start, a sweeping left-hand turn around Tattenham Corner, a downhill straight and a stiff rise in the last few hundred yards.
Wings Of Eagles (left, pink cap), ridden by Padraig Beggy and trained by O'Brien, was the 40-1 outsider who clinched Britain's richest race in 2017. The Derby was worth £1.625 million in 2017 with the winner receiving £921,500.
Wings of Eagles joined an illustrious list of Derby winners which includes superstars such as Sea Bird, Nijinksy, Mill Reef, Nashwan, Shergar (who won by a record 10 lengths) and Galileo. Legendary jockey Lester Piggott won a record nine Derbys between 1954 and 1983.
The area known as the Hill offers free spectating and multiple other attractions for Derby goers.
It's a far cry from the Royal Box, from where generations of British monarchs have watched the race unfold. (From left to right: King George VI, Princess Elizabeth (later Queen Elizabeth II), Queen Elizabeth (later Queen Mother) and the 16th Duke of Norfolk pictured at Epsom in 1948).
Back in the 1920s, a day out at The Derby was a must for many Londoners.
The St. Leger, first raced in 1776, is the oldest of the five Classics and takes place at Doncaster in the north of England in September. It's also the longest of the Classics at a mile-and-three-quarters. Ryan Moore rode the colt Capri (center) to victory for O'Brien last year.