A senior member of the Ratana Church says organisers of the annual festivities at the Ratana Pa near Whanganui are preparing for a busy day.
The celebrations mark the birthday of the church's founder, Tahu Potiki Wiremu Ratana.
Church executive committee head Waka Paama says Monday was quiet at the pa but he expects that will change on Tuesday as the celebrations get underway.
Among those expected to attend the opening day are Maori King Tuheitia, the Tuwharetoa Paramount chief, Sir Tumu te Heuheu, along with politicians - including National and Labour Party leaders.
Mr Paama says the Governor-General, Sir Jerry Mateparae, is expected to attend on Wednesday.