The fifty-two (52) remaining Oppenheimer telegraph poles are located along 4.7 kilometres of the original Overland Telegraph Line route and can be accessed by the public via a 1.5 kilometre long walking trail.

The Frew Ponds Overland Telegraph Line Oppenheimer Poles, are associated with the construction of the original Overland Telegraph Line (1870 - 1874). The fifty-two (52) Oppenhiemer poles located within the Frew Ponds Memorial Reserve are significant to the Territory as a remnant of the original line, and present tangible evidence of the construction methods and materials used in the construction of the 3,000 kilometre line from Port Augusta to Darwin that saw the end of Australia’s isolation. The heavy galvanised iron telescopic Oppenhiemer poles display a style of technology no longer practised and are a symbol of human ingenuity in solving the problem of transporting large numbers of sturdy termite resistant poles through inhospitable country.

The Oppenhiemer poles are a tribute to the vision of South Australia’s Post Master General, Charles Heavitree Todd, who was responsible for the construction of the telegraph line, and also the contributions made by the overseers, construction teams, line operators and linemen, all of whom, played a vital role in fulfilling this remarkable engineering feat.