 All 561 (535+5+10+8+3) current, obsolete or proposed Hundred names are listed in South Australia's official online gazetteer "Placenames Online".The city of Adelaide is located in the Hundred of Adelaide in the County of Adelaide.The County of Adelaide held at least 60% of South Australia's population between 1855 and 1921; the figure rose to 70.6% in 1966.