PHOTO: FONTERRA
Registration is required for the open day, which is being held from 10am-2.30pm on Saturday.
Operations manager Richard Gray said it was a rare chance to look behind the scenes of New Zealand's oldest dairy processing site.
Established in 1886, Edendale was the first factory in New Zealand to export refrigerated cheese and butter.
It now employed 670 people and could process 15 million litres of milk a day, Mr Gray said.
About 14 million bags of milk powder were exported from the site each year.
In 2016, Edendale was named the most energy-efficient dairy manufacturing site in New Zealand.
