Named after King William IV in 1837, it is historically considered one of Adelaide's high streets, for its focal point of businesses, shops and other prominent establishments.

[2] It is historically considered one of Adelaide's high streets, for its focal point of businesses, shops and other prominent establishments.

[citation needed] In August 1977, the first bus lane in Adelaide opened along King William Street from Victoria Square to North Terrace.

[3] The name King William is applied several times to the continuous stretch of road that begins in the inner southern suburbs and terminates in North Adelaide.

[citation needed] The road continues north to National Highway 1 as O'Connell Street, but the name King William is not again used.

In 2018, another expansion of the tram routes replaced the turn at the intersection of North Terrace and King William Street with a junction, and a short spur to a stop outside the Adelaide Festival Centre as well as an eastward extension along North Terrace to the Adelaide Botanic Garden.

[11] The theatre was located on the north-east corner of King William and Carrington Streets, with main entrances on both, opened in February 1911 and closed in 1928.

[18] With its entrance in Carrington Street, the ballroom was open to "suitably attired" members of the public each Wednesday and Saturday night,[22] and competitions were held there.

[10] Notable performances at the Warner include the Eleo Pomare Dance Company of New York City in 1972,[26] Don's Party in 1975,[27] and The Rocky Horror Show in 1977.

[30] The facade of the Sands & McDougall Printers and Stationers building at 64 King William Street, Adelaide is an excellent early example of Art Deco architecture in South Australia.

The facade of the 19th-century neoclassical building was redesigned in 1933, and was listed on the South Australian Heritage Register in December 2020.