They'll be breaking out the champagne at Hazelbrook and Woodford on Thursday as the new section of highway is finally opened.
Although the 3.2-kilometre stretch has taken more than 30 times as long as William Cox's team took to build the first road from Emu Plains to Mt Victoria, it is now complete.
But the work is not. As the president of the Hazelbrook Association, Angela Lougheed, told the Gazette, there is still construction of a plaza at the end of Memory Park, there are seats and lights to install and plants to be planted.
"But we'll still be celebrating," Ms Lougheed said. "We're trying to decide how many balloons and how much champagne we need. I think this stretch has taken longer to complete than anywhere else, not only in the state but in Australia."
And she said the community could thank the volunteers with the Hazelbrook Association, who have negotiated and petitioned and written to and lobbied politicians, the RTA and later RMS as well as the council to get the best result possible.
The association had fought on every aspect of the upgrade, Ms Lougheed said, from the design, to plantings, traffic lights, the inclusion of a pedestrian crossing outside the station, even over having sandstone walls rather than the bags of rocks that adorn other retaining walls on the highway.
"If they [fellow association members] hadn't given their time, the community wouldn't have achieved such a good result," she said.
Blue Mountains MP Roza Sage echoed Ms Lougheed's remarks.
"Without involvement from passionate residents who care deeply about their community, we would not have reached this point. I have welcomed their input and enjoyed working with them and representing their interests to achieve a positive outcome."
"This has been a challenging project and I would like to thank the community for its positive input and patience throughout," said Mrs Sage.
The road-building marathon began in 2006 when the railway underpass was started and suffered a major setback in 2012 when Reed Construction went belly-up.
Its completion means only the section around Bullaburra remains to fulfil the decades-long dream of four lanes from Emu Plains to Katoomba. It is due to be completed by next year.
The Hazelbrook-Woodford stretch includes dedicated turning lanes, upgrades to key intersections and the much-commented on pedestrian bridge to Hazelbrook station. Mrs Sage said a shared pedestrian and cycle path has also been completed along the length of the highway.