The borough council is planning the event in town centre streets on Saturday June 9 between 10am and 4pm. It is part of the Big Lunch jubilee celebrations and everyone is invited.
People can either bring their own lunch to eat at one of the designated seating areas throughout the town or can buy food at the party. There will also be a traditional British street market offering a wide variety of food and drink.
Entertainment throughout the day includes a parade of giant queens, and traditional entertainment including swing boats, helter-skelter, knobbly knees competition, bingo and a Punch and Judy show. Visitors may also spot a Dr Who Dalek.
A flotilla of boats will also sail along the River of Life in Bridge Street.
Cllr Mike Hannon, deputy leader of the council, said: “This is going to be an historic event that people will remember for a very long time and I hope that as many people as possible come along and join in. We’ve got some fantastic entertainment planned to help everyone get into the party spirit and to bring our communities together for what promises to be a wonderful day.
“This event will follow all the local street parties that will have taken place the weekend before and will be a marvellous end to all the celebrations.”