Historically, it is notable as a site for the mining of gypsum and since 1970, the majority of the land within the current extent of the locality is within the protected area called the Dhilba Guuranda–Innes National Park.

Water for grazing was sourced from wells fed by “natural springs.” Wells were established at Pondalowie Bay and Browns Beach during the 1850s and allowed “the establishment of sheep stations at Cape Spencer, Carribie and Stone Hut in the 1860s.” Cropping was carried out within the locality with “poor yields due to the intense coastal environment and soil infertility.” After 1927, land under cultivation increased due to “a better understanding of the importance of trace elements (mainly manganese).”[13] In 1889, the mining of gypsum began at Marion Lake by the Australian Gypsum and Whiting Company who developed infrastructure both at the lake and at the township of Marion Bay including a railway connecting both the mine and the town.

It is reported that six million tonnes (6,000,000 long tons) of gypsum was extracted from sites at Marion, Inneston and Spider Lakes between the years 1905 and 1973.

The national park was enlarged during the years 1977, 1984 and 1993 in “response to significant recreational use.”[15][16] Land in the locality was originally known as Cape Spencer.

[14][24][25] Inneston is located within the federal Division of Grey, the state electoral district of Narungga and the local government area known as the Yorke Peninsula Council.