Descendants of a soldier at Gallipoli who wrote a letter to family at Dardanup are pleased the document will be displayed at Bunbury Museum and Heritage Centre.
The South Western Times reported in February on Bunbury resident Mark Mazza's incredible find at a Dardanup dump during the 1980s.
The letter was written by Joseph Thomas Harris and describes his experience at Gallipoli.
His descendants met on June 30 - exactly 100 years since the letter was written - to decide the document's future.
Dardanup resident Gwen Wells, whose grandfather was Mr Harris' brother, said she was pleased that the letter would be displayed at Bunbury Museum and Heritage Centre, which is set to open later this year.
"I think if it went to the Australian War Memorial museum, it would be lost amongst so many other letters - but it is more significant if it is displayed in Bunbury," she said.
"Most of the family members felt the same way and it is here for future generations to look at."
Mrs Wells said she was amazed when she saw the Times story and was thankful for Mr Mazza's actions to save the letter.
"He set the meeting up with the family and he has done so much," she said.
"So I sent him a letter of thanks for saving the letter."
Museum curator Lauretta Davies said the letter would be appropriately preserved and displayed.
"One of the first displays at the museum will be a World War I exhibition and this letter is a perfect example of the history that will be available for everyone to appreciate," she said.
Mr Mazza said he was pleased the letter would be preserved at the museum for future generations.
"I've been the custodian of the letter for over 30 years so I'm relieved it is going to a place where it will be properly preserved," he said.
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