Security checks are underway in the Windsor as the town prepares for the Queen's Birthday and the arrival of US President Joe Biden.
Thames Valley Police said that officers and search dogs had been deployed in the royal borough ahead of the weekend's events.
Firearms officers have already been out on patrol in the area. Security sweeps have also been carried out at Royal Ascot, which is also running this weekend.
Duke of Kent to join Queen at parade
The Queen's official birthday parade, a slimed down version of Trooping the Colour, will be held inside the castle walls on Saturday.
It's the second year in a row that this paired back parade is being held. The event would normally take place on Horse Guards Parade in London, involving hundreds of troops, horses and an RAF Flypast.
The Duke of Kent, Colonel, Scots Guards, will join the head of state for the ceremony and the Queen’s Colour of F Company Scots Guards will be trooped through the ranks of guardsmen on parade.
It will feature troops who have played an integral role in the NHS’ Covid-19 response and those who have been serving on military operations overseas.
Queen to meet host her 13th US President at Windsor
The President and the First Lady Jill Biden will arrive on Sunday to meet Her Majesty, following the conclusion of the G7 summit in Cornwall.
It's the first time the Queen will meet Biden in person since he was elected to office in November last year.
During the Queen’s 69-year reign, there have been 14 American presidents – from Harry S Truman to Biden.
Following Sunday's audience she will have met all of them except Lyndon B. Johnson.
She met Biden’s predecessor Donald Trump when he made a state visit to the UK in June 2019 in the last days of Theresa May’s premiership.