There’s no track to the Boundary Trig Station, but it’s reached via a relatively short walk through light scrub from Mona Vale Road. The trig is on the very edge of Garigal National Park.
It doesn’t feel like the trig is on a high point, nor is there any view… but the trig station is in fairly good condition, with its concrete base, metal post and vanes intact.
Getting to Boundary Trig
The easiest way to reach this trig station is by parking on the shoulder of Mona Vale Road (on the westbound side) and taking a fairly direct line through the bush to the trig.