“The disappearance of the Beaumonts is easily Australia’s greatest unsolved ... Picture: Naomi Jellicoe Arnna, Grant and Jane Beaumont disappeared from Glenelg on January 26, 1966.

Ground will be excavated at the former Castalloy factory site in Adelaide for the third and final time to look for the missing Beaumont children before the land is developed.

Jane, Arnna and Grant – went missing but it’s a tragedy and a mystery that still fascinates South Australians and the hunt ...