Thousands are expected to attend street parties and other large-scale events planned county-wide with more than 200 local roads in towns and villages closed to vehicles.
It all kicks off with beacons being lit on Thursday (June 2) to mark the historic occasion.
Crowds are also expected to flock to the Crick Boat Show and Northampton Beer Festival — which both return for the first time since before the Covid pandemic in 2019 — and the Corby Pole Fair, which is held every 20 years.
Local Policing Chief Inspector Pete Basham said: “We’re expecting to be extremely busy and so we’re making the usual appeal for people to enjoy themselves safely, and to respect staff and other attendees at these events, as well as our own officers, PCSOs, staff and Special Constabulary, who will be out and about throughout the weekend.
“We know across the county that there are lots of celebrations planned to mark the Platinum Jubilee as well as other public events over the extended bank holiday.
“We want to ensure that we can all safely celebrate this once-in-a-lifetime event and will have increased patrols taking place across the county to make sure people are celebrating sensibly and responsibly."
Chief Inspector Basham also warned the force will be ready to crackdown on any anti-social behaviour.
He added: “Many people will be celebrating with alcohol, particularly if the weather’s nice.
"We urge everyone to play their part to ensure the long weekend runs smoothly by looking out for each other."
"It should be a celebration. If your behaviour is violent or anti-social, it could have consequences for you, your family and friends, as well as any events you’re attending, which could include the potential for it to be closed.
“No-one wants that – we all want to enjoy the holiday while celebrating the Queen’s long reign. So, please don’t ruin it for everyone else.”
■ If you need to call the police during the weekend but it’s not an emergency, using the Northamptonshire Police website helps keep the 101 non-emergency number clear. Always call 999 in an emergency or if you see a crime in progress.”