A watched cliff never collapses?

In early 1931 sightseers were transfixed by the plight of a landform in dire peril that was clinging onto the upper section of Katoomba's Dog Face Rock.

During the Great Depression, the teetering 'leaning rock' offered cheap entertainment of the most majestic kind. A 'free for all' for sightseers on foot and a boon to the local hire car industry, the calving of a sandstone escarpment galvanized newspapers throughout the land.

What triggered the series of landslides that created Dog Face Wall as it is now known? In short, the downfall of the outer cliff had much to do with the downturn in economic growth and the pressing need to turn a dime.

Four weeks in the undermining, five months in the offloading and almost 90 years in the 'recovery' phase, the resulting Dog Face Wall, a popular climbing destination, is the legacy of one of the Blue Mountains' most impressive 'escarpment failure' events.

Kirribilli's Barbara Cameron-Smith retells the story of The Leaning Rock of Katoomba, following in the footsteps of others who have recorded the story (especially in the book The Burning Mists of Time: A Technological and Social History of Mining at Katoomba, by Philip J. Pells and Philip J. Hammon).

"Thanks to the meticulous research by the two Philips I was able to incorporate their findings about what triggered the landslide into The Leaning Rock of Katoomba - Tragedy of Nature or a Man-made Landslide? booklet."

The Katoomba landslide could be classed as one of Australia's first iconic 'big things', a must not miss event for inquisitive thrill seekers. The looming geological event was a cash cow for local businesses think cafes, trains, buses, petrol stations and accommodation outlets for starters, not to mention opportunistic locals peddling things like cold drinks and fresh fruit.

Reported in syndicated papers around the country, the imminent landslide was a tourist destination of the natural kind, a colossal 'calving', not of an ice sheet but of a supposedly rock solid sandstone cliff.

The fresh face revealed by a series of 'resurfacing' events has long been obscured by the passage of time. But for four months in 1913, the newspapers of the day hung on the fate of the so-called Leaning Rock of Katoomba, a rock that was clearly in peril.

Ms Cameron-Smith said she had been "fascinated by the landslide since childhood as our family's annual holiday was spent in and around Katoomba".

"And whenever we walked the mountain passes, we were cautioned by our parents to make haste below the sheered off cliff as it still had a reputation as a potentially dangerous site."

The author studied earth sciences at university (including geology and geomorphology), and joined the Macquarie Mountaineering Society.

"The pull of the Blue Mountains walks, canyons and cliffs intensified. As a member of the Sydney Rock Climbing Club, I enjoyed close encounters with climbing routes on Narrowneck, Mt Piddington and later in the Wolgan Valley. At the time, Dog Face was held in awe by the climbing fraternity, considered only scalable by mechanical means, as in, impossible to climb without aid."

She wrote the book to make "some kind of chronological sense of all the photos (from the State Library of NSW and Blue Mountains City Library) I could lay hands on in order to piece together what happened where on the landslide site".

"What became crystal clear was that the so-called landslide was not just one cataclysmic event but a drawn out series of rock falls and slides over a number of months."

The booklet is now available at the Blue Mountains Heritage Centre Govetts Leap, Glee Books Blackheath, Megalong Books Leura, The Turning Page Bookshop Springwood, Paddy Pallin Sydney. It can also be ordered online post free at sales @envirobook.com.au.