Royal wedding: Tough Windsor security measures to be introduced
Windsor will be cordoned off and people will have to go through full body scanners to get to the town as part of the royal wedding security measures.
A "screening and search" regime will be introduced in the run-up to Prince Harry's marriage to Meghan Markle at St George's Chapel on 19 May.
Police would not confirm the exact date of when the secure zone would be implemented for security reasons.
More than 100,000 people are expected to arrive in the town for the big day.
Police said large items deemed a "security risk" would be banned in the town, including tents, following plans by groups on social media to stage a "sleepover" protest against removing rough sleepers from the streets.
The "extensive" measures are part of the policing plan to "deliver a safe, secure and happy event for everyone".
Thames Valley Police said automatic number plate recognition technology, CCTV and "hostile vehicle mitigation barriers" were being put in place.
Nearly all officers from the force will be working on the day with all leave requests being denied for the weekend.
Shops and buildings will be searched in the days leading up to the wedding and plans are in place to stop trains from calling at Windsor station if the numbers of people in the town causes a "public safety risk".
Supt Jim Weems, tactical commander for the wedding, said "public safety" was the force's main priority and added he expected the town to be full by about 9:00 BST on the day.
Police officers, both armed and unarmed, search dogs, police horses and the National Police Air Service will increase their presence in the coming weeks.
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The force said the public "should be reassured and not alarmed by this, as these are all part of our measures to keep people safe".
A number of other forces, including British Transport Police, the Met and Surrey Police, will also be involved in the operation as well as the Army.
The Ministry of Defence announced more than 250 members of the Armed Forces will perform ceremonial duties at the wedding and said the regiments and units selected "all have a special relationship with Prince Harry".
They include the Household Cavalry, the Army Air Corps, the Royal Gurkha Rifles and the Irish Guards.
The police said it would take "several hours" for people to leave Windsor after the restricted zone is lifted.
Assistant Chief Constable David Hardcastle said "conversations are going on" around the cost of policing the event and who is picking up the bill, but he confirmed that some of the cost will fall on the Thames Valley taxpayer.