Snipers are on rooftops with soldiers and armed police patrolling the streets below as a £30million ring of steel today surrounds Windsor Castle ahead of the royal wedding.
Police, the Army and undercover members of the security services are ready ‘do whatever is necessary’ to prevent any attack on Harry and Meghan’s big day, including shooting to kill.
The 2.6-mile route the couple will travel from St George’s Chapel to Windsor Castle is lined with sharpshooters on top of buildings and other vantage points.
Police and soldiers carrying automatic weapons will also line the streets ready to fire if necessary and are already patrolling the roads, which have crash barriers used to stop vehicle-based terror attacks.
With the UK’s terror threat level at severe the cost of security for the first major royal wedding since 2011 is expected to reach up to £30million and the bill will be picked up by the taxpayer.
It is Thames Valley Police’s biggest ever operation and they are relying heavily on Scotland Yard and MI5 for support.
It came as superfans camped on the streets overnight to secure their spots to see the procession through the Berkshire town tomorrow.
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Police spotters and snipers are lining the 2.6mile route set to be followed by Meghan and Harry and are ready to shoot to kill
A police officer watches on from the rooftops of Windsor during one of Britain’s biggest security operations for years
Soldiers have also been drafted in to secure a ring of steel around Windsor Castle ahead of the biggest UK royal wedding since 2011
Armed officers are on patrol and MailOnline understands there also undercover officers and MI5 ready to act if needed
Excitement ahead of the wedding is reaching fever pitch today as Americans and Brits pose outside Windsor Castle
Superfans camped on the streets overnight to secure their spots to see the procession through the Berkshire town tomorrow
A guide to the timings of the event on Saturday, from when the first guests arrive at 9.30am to the reception at 7pm
Armed police and specially trained sniffer dogs are patrolling the streets of the royal town, with squadrons of uniformed officers with machine guns toured the town in rotation.
Their colleagues are checking drains, bins and any other potential hiding places for bombs as the Berkshire town was turned into a fortress.
Thames Valley Police and the Metropolitan Police – who guard the Royals – used the dress rehearsal yesterday to assess any potential security threats or bottlenecks and crowd surges.
As many as 100,000 visitors are expected to flock to the Berkshire town this weekend – which has a population of 35,000 – to catch a glimpse of the newlyweds.
Wedding planning service Bridebook say it could cost as much as £32million to ensure the event remains safe.
The amount is more than double the security needed for the 1981 wedding between Prince Charles and Diana Spencer which was estimated to have cost £4million – which equates to around £12million today.
Extra police from around Britain are being called upon to help ensure the event goes off without a hitch, as crowds will fill Windsor to catch a glimpse of the royals.
Since Prince William’s wedding the UK has experienced a surge in terror threats, meaning the cost of Harry’s nuptials outside of the city will be much higher.
The couple’s decision to invite more than 2,000 members of the public to attend celebrations at Windsor Castle has also increased security costs.
The Queen revealed has said she and the rest of the royal family will pay for the traditional wedding costs like the ceremony, flowers, music and the reception – but security is likely to be paid in full for by the taxpayer.
Beautiful start: The sun pictured rising above Windsor Castle this morning as excitement in the Berkshire town reaches fever pitch
Camp out: Royal fans stirring this morning after sleeping just metres from Windsor Castle ahead of Prince Harry and Meghan Markle’s wedding tomorrow
Early start: One fan, wearing a union jack tiara fixes her tent after spending the night in front of barricades to get a prime position ahead of tomorrow’s nuptials
Enthusiastic: Supporters pictured slouched on camping chairs while one slept draped in towels and covered by a cardboard box
Front seats: A beaming well-wisher encapsulated in a bright blue sleeping bag smiles to the photographer after snapping up a top spot in front of the barriers
Windsor’s M&S is also cashing in on the big day by renaming the high street store Markle and Sparkle
A man drives a car decked in Union Jack colours while people snuggle up in sleeping bags by the side of the road in Windsor
A woman reads a newspaper outside Windsor Castle as she prepares to camp out at the royal wedding venue
Two women sit on chairs decorated with Canadian flags as they try to keep warm outside Windsor Castle overnight
People keep warm in coats and Union Jack-decorated bobble hats as they prepare to spend the night outside Windsor Castle
A woman sips from a cup while she sits in front of a display of Union Jack flags outside Windsor Castle
Excitement is reaching fever pitch for royal superfans who have been sleeping on the streets of Windsor as their long wait for the wedding enters its final day.
The enthusiasts, who eagerly watched hundreds of members of the armed forces march through Windsor in a dress rehearsal yesterday, were seen snuggling up in sleeping bags on the pavement, two nights before the service at St George’s Chapel.
Thames Valley Police are enforcing a no tent rule in the run-up to the big day for security reasons, forcing some people to sleep in the open air or on fold up chairs.
One keen driver was seen at the wheel of a Union Jack-decorated car while others carried flags with Harry and Meghan’s faces on them.
The visitors, determined to get the best view of the royal couple, have set up camp behind the barriers on the route that the royal procession will take through the Berkshire town.
Yesterday a full rehearsal took place in front of thousands of people.
Beating drums of a military brass band heralded the arrival of the wedding cortège at Windsor Castle during the rehearsal, followed by different regiments of the Army and Royal Navy, including a platoon of Gurkas.
Police shut roads as the military and other emergency services geared up for the big day, while the horse-drawn royal carriage left Windsor Castle surrounded by a mounted platoon of the Household Cavalry.
The procession was followed by a team from the Diplomatic Protection Group in a black Range Rover and by a green Land Rover.
The Ascot Landau carriage also took part in the procession, which has been chosen by the newlyweds for their open top tour of the town when they are husband and wife.
It is used in official and ceremonial state events, and will pulled by Windsor grey horses. The horses will be the same one’s used on Saturday.
There are five carriages like the one seen, which are kept in the Royal Mews. They take their name because they are used during the Queen’s procession at Royal Ascot ever year.
Kensington Palace confirmed that the armed forces taking part included the Irish Guards, the British Army, including members of the Gurkha regiment, the Army Air Corps, the Royal Navy and the Household Cavalry.
An aerial view of the procession with Windsor Castle in the background showing thousands of people had lined the streets to come out to watch
The carriage leaves Windsor Castle and was drawn by two horses that will be used on Saturday
Seaman from the Royal Marines Band Service took part in the procession underneath clear blue skies and warm temperatures
Royal well-wishers watched on from behind metal barriers as members of the Household Cavalry on horseback made their way through Windsor
The procession travelling along the Long Walk, with TV broadcast areas visible to the left that will beam footage of the event around the world
The Band of the Irish Guards march below huge Union Jack flags that adorn the High Street
The procession, cheered on by thousands of spectators march past Windsor Castle as they make their way along the procession route
The final stages of the procession involving Prince Harry and Meghan will end on the Long Walk, pictured
Lynda Moore, 70, from Ontario, Canada, had come to Britain especially for the royal wedding and was watching the rehearsal.
‘It’s just so great,’ Mrs Moore told MailOnline.
‘We all live the royal family in Canada. As you know Queen Elizabeth is our monarch too. I think Prince Harry is a lovely young man and Meghan is very beautiful.’
Mary, 62, from Auckland, New Zealand, had also come to the UK because of the marriage.
The military marched through the Union Jack lined streets watched on by thousands of royal fans desperate to get a glimpse of what Saturday will bring