In 1993, the southern end of the motorway was extended to Mill Road, near Bombay. The extension bypassed the traffic light-controlled crossroads at St Stephens, known to be an accident blackspot and causing delays of up to two hours during holiday periods. Accompanying the extension was the building of the first part of the Waikato Expressway, which allowed traffic from the Southern Motorway to have a clear run as far as the State Highway 2 interchange on the south side of the Bombay Hills.