The Great Western Highway is a critical road link between Sydney and the Central West and traverses the sensitive Blue Mountains environment through several towns and villages. The NSW Government is investing EUR1.60 bn (AUD2.5 bn) towards a staged upgrade of the highway between Katoomba and Lithgow to provide safer, more efficient, reliable journeys in, around and through the Mountains, and to better connect the communities of the Central West. The Great Western Highway Upgrade Program, listed by Infrastructure Australia as a priority initiative, proposes to deliver approximately 34 kms of four lane highway between Katoomba and Lithgow, with the route to be progressively upgraded in stages. Investigation work are now underway - in the Katoomba, Medlow Bath, Blackheath, Mount Victoria, Little Hartley, Hartley, South Bowenfels and Bowenfels areas - to make an 11-km tunnel the central component of an upgraded Great Western Highway, joining together the already committed tunnels to bypss Blackheath (4.5km) and underneath Victoria Pass (4 km) - one of the steepest roads in NSW - through the Blue Mountains. Ongoing works include taking water and soil samples using a drill mounted on a truck, installing noise monitors, biodiversity studies, traffic studies and environmental surveys. The eastern entry for the new long proposed tunnel will be on the outskirts of Blackheath to minimise impacts on local homes and be built in a section of National Park land to the south of Evans Lookout Road. At the western end, the portal location in Little Hartley has been modified to improve safety and reduce property impacts in the valley. Transport for NSW is engaging with National Parks about the upgrade’s impacts on land adjacent to the proposed portals. Neither portal would impact the Greater Blue Mountains World Heritage Area. If the current investigations into a long tunnel determine that it isn’t viable, NSW Government will proceed with a tunnel at Blackheath and a tunnel at Mount Victoria. Construction on the Great Western Highway Upgrade is expected to start at Medlow Bath in 2022, with the full upgrade expected to be completed within 8 to 10 years. Last December Aurecon and Jacobs Arcadis Joint Venture secured the contracts to refine the design and prepare environmental assessments for easter and western section respectively. For more information on the Great Western Highway upgrade between Katoomba and Lithgow visit https://www.nsw.gov.au/.