An inscription on the back reads: "To Robert Landreth. A souvenir for good and faithful work at The Camp. From W.J.M. Larnach. March, 1876".
His legacy is etched in stone to this day on the peninsula, where the stone walls he built still stand.
The home he built at Cairntop is still a residence today and a cottage he and son James built near Middlemarch in 1887 also still stands.
Mr Landreth worked as a stonemason for eight years at "The Camp", as Mr Larnach called his stately home, from 1863-71.
The oldest descendant attending the reunion, which will be held on Wednesday and Thursday, is 91-year-old Tom Landreth, of Cromwell, whose grandfather was James, Mr Landreth's eldest son.
Tom Landreth also attended the 100th and 125th Landreth family reunions at Larnach Castle.
"The idea is to visit Larnach Castle, where Robert did quite a bit of work, and we'll also visit the first house he built, at Cairntop," Mr Landreth said.
"We're expecting over 150 people from Australia and all over New Zealand."
Descendants will also visit Pukehiki Church, where a plaque commemorates Mr Landreth and his wife, Helen.
Up to seven of the Landreths' great-grandchildren, who are now in their 80s and 90s, were also expected to attend.
