Iron ore was first transported by bullock wagon to Port Augusta, where it was loaded on to 200-ton barges.

These allowed the direct loading of ships which could transport the ore across Spencer Gulf to Port Pirie.

21% of the steel required for the construction of the Sydney Harbour Bridge[13] was quarried at Iron Knob and smelted at Port Kembla, New South Wales.

[17][18][19][20] In the financial year 1935–36, 291,961 tonnes of ore from Iron Knob was shipped there via the seaport of Whyalla.

[22][23] Waterfront workers and seamen protested against the export of iron ore to Japan, leading to strikes and arrests.

[25] In 1943, the iron Knob deposit was still delivering an average ore grade of 64 percent metallic content.

[26] Additional deposits of iron ore were developed by the Broken Hill Proprietary Company further south along the Middleback Range.

[needs update] In the early days of mining at Iron Knob, ironstone was carted by oxen to Hummock Hill (renamed Whyalla in 1914).