The Holy Trinity Cathedral in Auckland is to be consecrated.
The cathedral at the top of Parnell is a landmark in the city, and has hosted major events like the funeral service for Sir Edmund Hillary, but has never been finally finished and consecrated.
The land was purchased in 1843 and the cathedral foundation stone was laid in 1957.
The Anglican Bishop of Auckland, Ross Bay will lead the Service of Consecration at 3pm on Saturday.
Holy Trinity Cathedral will be the last cathedral to be consecrated in New Zealand, signifying that the building has been completed and is debt-free.
Jo Kelly-Moore, who led the project to complete the cathedral before leaving to be Archdeacon of Canterbury in England, will attend.
The project to finish the cathedral included a new organ, completing the 150-seat Bishop Selwyn Chapel, and the removal of the bridge that linked the old and new parts of the cathedral.
Bishop Selwyn arrived in New Zealand as the first Anglican Bishop of New Zealand in 1842.