Getting started
From the end of Trevors Ln, Cherrybrook, the walk passes the 'Berowra Valley Regional Park' sign and follows the management trail beside the houses. The walk almost immediately passes around a gate and arrives at an intersection with another management trail.
From the intersection, the walk follows the management trail, directly away from the houses. After a short distance, the trail reaches an intersection with another management trail, signposted '92A/92B ...'.
From the intersection, the walk follows the 'ST22/23' arrow, going gently up the hill, along the management trail. After a very short distance, the trail passes under some high voltage powerlines and immediately reaches an intersection with a bush track, to the right, and management trail, to the left.
From the intersection, the walk follows the management trail away from the high voltage powerlines, leaving the visible tower to the left. The trail descends gently, through pleasant forest (ignoring an unmarked bush track to the right) and reaches an intersection with another management trail, signposted '92A 92B/16'.
From the intersection, the walk follows the level management trail, leaving the '92A 92B/16' signpost behind on the left. After a short distance, the trail passes a clearing, to the left, and descends for a while before arriving at a large, flat rock outcrop, the western edge of 'Refuge Rock'.....

Refuge Rock
Refuge Rock is a large area of rock outcrops and platforms, at the end of the Refuge Rock walk near Cherrybrook. This area has a great atmosphere and is a nice spot to explore or relax, close to the suburbs, but feeling a million miles from it. The various rock platforms extend for hundreds of metres in all directions. At the far south-east edge of Refuge Rock is a natural arch, know as 'London Bridge'. Refuge Rock was used as a target area during military training around WWII. There are a number of visible marks in the rock surface from mortar shells.

Natural Arch
This natural arch, known locally as 'London Bridge' is at the south-eastern edge of Refuge Rock, near Cherrybrook. The arch is formed below a long, narrow block of rock at the edge of a larger rock platform. To see the arch, you walk down through the narrow chasms separating the block from the rock platform, to emerge underneath the arch. The arch itself, and the area around it is beautiful.