The city of Lisburn will host the South Antrim Combine Twelfth for the first time in seven years.
A total of seven districts – totaling more than 70 individual lodges - will participate in the parade, led by Lisburn brethren, who will be followed by Magheragall, Ballinderry, Derriaghy, Hillsborough, Aghalee and Glenavy.
Orangemen, women and juniors will be accompanied by approximately 50 bands for the colourful occasion, which typically attracts a large number of spectators.
The Lagan Valley has special significance on the Twelfth, given King William visited Lisburn Castle and inspected troops at nearby Blaris Moor, before stopping at Hillsborough, on route to the Battle of the Boyne in 1690.
The event is scheduled to get underway at 11.30am, with the parade commencing from the assembly point of Wallace Park.
It will then proceed through the city via Magheralave Road, Railway Street, Market Square, Market Street, Smithfield Street, Market Place, Governors Road, Thiepval Road, Prince William Road and Knockmore Road to the demonstration point at Ballymacross Playing Fields.
Among the lodges on parade will be LOL 1981, who celebrate their 40th anniversary this year.
Ballymacash LOL 317 will also step out with a new banner, depicting scenes from the Battle of the Somme.
It was shortlisted in the Best New Banner Award category at this year’s Orange Community Awards.
The return parade is due to leave Ballymacross at 4.15pm, making its way back towards the city.