Canterbury Museum has been bequeathed $10 million in the will of a man from Blenheim, who died in a house fire last year.
Arthur Henry Harrison instructed the money be put into a charitable trust to buy historical items for public display.
The Museum says it's extremely grateful for the donation, although it says checks had to be made to ensure Mr Harrison's will was up to date.
He was born in Sydney in 1917, and moved to New Zealand 20 years later. He and his wife did not have any children.
Canterbury Museum director Anthony Wright says Mr Harrison's legacy in the community will live on through the charitable trust.