The Metrorail Gauteng commuter rail system connects central Johannesburg to Soweto, Pretoria, and most of the satellite towns along the Witwatersrand. The railways transport huge numbers of commuters every day. However, the Metrorail infrastructure was built in Johannesburg's infancy and covers only the older areas in the city's south. The northern areas, including the business districts of Sandton, Midrand, Randburg, and Rosebank, are served by the rapid rail link Gautrain.