Melissa Stewart McSeveny submitted the Route:
From the Jenolan Caves to the Nepean River, including the Six Foot Track, Mount Solitary, Ingar, The Oaks and Darks Common, before ending at Regatta Park Emu Plains.
From an iconic landmark on the south western side of the Blue Mountains (Jenolan Caves) to the foot of the Blue Mountains on its eastern side (Nepean River). It traverses the entire length of the Blue Mountains World Heritage National Park along the southern side of the ridgeline of settlements, passing over the iconic Mount Solitary. This route has been spoken about by local runners as a possible FKT route for up to 20 years, but has never been done to my knowledge, or that of the local running community.
The route on Google Maps:
Some info about the Jenolan Caves: https://www.visitnsw.com/destinations/blue-mountains/oberon-area/jenolan-caves
Some info about the Blue Mountains: https://www.visitnsw.com/destinations/blue-mountains