County of Carnarvon is a cadastral unit located in the Australian state of South Australia which covers the full extent of Kangaroo Island. It was proclaimed in 1874 by Governor Musgrave in response to the demand for agriculture land on Kangaroo Island.

The Hundred of Dudley is a cadastral unit of hundred located in the Australian state of South Australia on Kangaroo Island and which covers an area of 300 square kilometres (117 sq mi) including the full extent of the Dudley Peninsula and some land to the west of the peninsula.