Royal wedding revellers will face airport-style security checks while metal barriers to deter vehicle attacks will be in place around Windsor.
Tens of thousands of spectators are expected to flock to the Berkshire town for today's event which is expected to be the largest ever policed by Thames Valley Police.
Assistant Chief Constable David Hardcastle, strategic commander for the wedding, said: 'We are proud to police the Royal Borough of Windsor and Maidenhead. The Force has a long history of policing royal events from the annual Windsor Garter Ceremony to state visits and more recently Her Majesty the Queen's 90th birthday.
'The wedding of Prince Harry and Ms Markle is no exception.
'We are working with our partners, local businesses and the community to deliver a safe, secure and happy event for everyone.'
Other security measures include an extensive network of automatic number plate recognition (ANPR) technology and CCTV alongside hostile vehicle mitigation (HVM) barriers to prevent the use of cars or vans in an attack.
In the coming weeks residents, local businesses and visitors to the town can expect to see an increased police presence, with police officers, both armed and unarmed, search dogs, the mounted section, the roads policing unit and the National Police Air Service joining forces.
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