Thousands of spectators are expected to pour into the town on Saturday as more than 2,500 representatives of the army, the navy and the Royal Air Force pay their respects to the Queen.
A parade through the town from the castle to the Home Park will include a tri-service guard of honour and six military bands, followed by the Queen and the Duke of Edinburgh themselves.
An awe inspiring flypast of 78 aircraft including helicopters, Hawks, the Battle of Britain Memorial Flight, the Red Arrows and Tornadoes will follow a special 'drumhead' service conducted 'in the field' at Home Park with specially composed music. The whole event will be broadcast live by the BBC.
From 10am Windsor Road will close at its junction with Queens Road, along with King Edward VII Avenue, Datchet Road, Thames Avenue, River Street north of the junction with Thames Avenue, Barry Avenue between River Street and Railway Viaduct, exit with Alexandra Gardens car park, Goswell Road at the roundabout with Charles Street and Arthur Road, Bridgewater Terrace and Goswell Hill.
All the closures will be lifted by noon, except for the B470 Windsor Road at its junction with Queens Road, Datchet, the B470 King Edward VII Avenue and B470 Datchet Road which will stay closed until 4pm.
The length of Sheet Street between the junction with Frances Road/Kings Road and Victoria Street will close for 10 minutes between 10.25am and 10.35am.
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