News Overtaking lane work in the pipeline 02/06/2022 Facebook Twitter Email The Department of Infrastructure and Transport map showing proposed upgrades for the Princes Highway in the Mount Gambier and Millicent areas as part of a $190m Federal and State Government commitment to the Princes Highway in South Australia. MOTORISTS travelling between Millicent and Mount Gambier on the Princes Highway will be pleased to hSubscribe or log in to read the rest of this content.