Royal Ascot is welcoming the Queen for a week of horse racing that will attract around 300,000 race-goers to the famous sporting and social event over the coming days.
The Queen regularly attends the horse racing meet, held over five days, and each afternoon travels up the course in a carriage procession with the Duke of Edinburgh, members of the Royal Family and guests.
Royal Ascot has honoured the Queen ahead of the week by re-naming a race to mark the monarch's 60-year reign. The Diamond, formerly Golden, Jubilee Stakes, will be run on Saturday - the last day of the sporting event.
A passionate horse breeder and owner, the Queen has entered one of her thoroughbreds, Carlton House, for the Prince of Wales Stakes being staged at the meet on Wednesday.
Royal Ascot is more than a sporting occasion; it is also a social and fashion event for the hundreds of thousands of spectators who will flock to the Berkshire racecourse this week.
This year, organisers have raised the bar in the sartorial stakes by tightening and clarifying the dress code at the annual summer event, including imposing a ban on fascinators in the royal enclosure.
The move comes amid criticisms of sartorial standards which have been loosely enforced in recent years, but help will be on hand from a team of specially trained "dress code assistants".
A selection of waistcoats, ties, pashminas and other items will be available at the turnstiles for those who need them.
In the royal enclosure, fascinators - which are often favoured by the Duchess of Cambridge - are no longer deemed acceptable.
Women will also be expected to wear skirts or dresses of "modest length" which fall just above the knee or longer. This clarifies previous guidance which stated miniskirts were "considered unsuitable".