In days of yore, bullock drays hauled timber from the cedar forests north of Yarramalong to Mangrove Creek where it was taken by boat to Sydney. This segment of the Great North Walk from Kulnura down to Yarramalong follows part of that old track, and if you listen carefully you might still hear the ghosts of those toiling bullockies from long ago.
Begin at the GNW trackhead on Greta Road, following the power line easement north into the valley. The descent is steep and the track badly eroded in places with lots of loose rocks, so take care not to go for a tumble.
Halfway between the third and fourth towers, the track turns sharply right, leaving behind the Desolation of Transgrid as it enters the beautiful glades of Bumble Hill. Wonder at the alternating landscape of open woodland and subtropical rainforest as your path contours its way around spurs and gullies, passing tall cliff faces laced with ferns, troll caves and the beautiful Hanging Garden before finally reaching GZ in a rocky outcrop just left of the track.
The cache is a 380ml Sistema with a pencil provided.
If you can arrange a car shuffle, it's well worthwhile continuing all the way down into Yarramalong township.