A number of feeder parades are scheduled to take place across the district in the morning and evening, including in Lurgan and Portadown.
There will also be parades in Gilford, Rathfriland, Dromore and Scarva.
In the Armagh area there are planned parades in Tandragee, Richhill, Middletown, Keady, Killylea and Armagh city itself.
“Road users are advised of the potential for delays in these areas which will be kept to a minimum,” said a PSNI spokesperson.
Apprentice Boys from right across Northern Ireland will be walking in their own areas before – and upon return from – the ‘Relief of Londonderry’ celebrations, which takes place annually on the second Saturday in August.