Beacons will be lit at Northern Ireland's highest peak and most westerly town later to mark the Queen's Platinum Jubilee.
The official four-day celebration of the 70th anniversary of the Queen's coronation will include street parties, exhibitions, church services and lunch events.
Thursday will mark the start of a long bank holiday weekend which will also include a visit from the Earl and Countess of Wessex.
The Royal couple are expected to carry out two engagements in the region on Saturday.
A gun salute will take place at Hillsborough Castle, the Royal family's official residence in Northern Ireland, while in Belfast the HMS Pembroke will be alongside for the weekend and open to visitors with pre-booked tickets.
The UK's most westerly town, Enniskillen in Co Fermanagh, will enjoy one of the busiest celebrations.
Visitors can enjoy a special exhibition at Enniskillen Castle which will include a maid of honour gown and page outfit worn by local people who played key roles at the coronation.
It will also host a special church service at St Macartin's Cathedral on Thursday evening where the Queen visited in 2012 during her Diamond Jubilee, before beacons are lit.
As part of 1,500 beacons being lit across the UK between 9.15-9.45pm, many locations in Northern Ireland will host a lighting including Titanic Belfast in the capital city and St Columb's Cathedral in Londonderry as well as the region's highest peak.
The Walking With The Wounded charity will hike a beacon up Slieve Donard in Co Down, while their colleagues do the same at the other UK peaks, Ben Nevis, Scafell Pike and Mount Snowdon.
On Sunday, big lunch events will be taking place across the region, including on the Shankill Road and in the town of Bangor, Co Down, which was made a city as part of the Jubilee celebrations.