Rail connecting Whyalla to Port Augusta is [[standard gauge]]. The national standard gauge system extends from Port Augusta to [[Darwin, Northern Territory|Darwin]], [[Perth]], [[Adelaide]] and other regional towns. A separate and isolated [[narrow gauge]] railway connects Whyalla to [[Iron Knob]] and extends to [[Iron Duke, South Australia|Iron Duke]] and other iron ore mines of the [[Middleback Range]]. It is privately operated for the exclusive use of [[Arrium|Arrium Ltd]]. Railways to Whyalla were originally built for the [[Broken Hill Proprietary Company]]. A new rail link connecting Port Bonython to the Whyalla standard gauge line is a component of the [[Port Bonython Bulk Commodities Export Facility]] proposal.