Jenolan's Eerie Shortcut to Underworld Wonders

A well-meaning person once said, "There are no shortcuts to anyplace worth going." They didn't know what they were talking about. A shortcut always takes you to where you really want to be.  Sixty-six years ago, at Jenolan we opened our own shortcut - a tunnel, named The Binomea Cut - allowing easy access to the stunning Orient Cave and the awe-inspiring Temple of Baal Cave.  At 400 feet (122 metres) long, when it opened, it was “The longest man-made tourist access tunnel in Australia. [i]” With so many natural tunnels at Jenolan (Australia’s largest cave system that is open to the public), why was a manmade tunnel even necessary?

Jenolan’s underground passages and caverns stretch kilometres into the limestone mountain.  The entrances to most of our spectacular caves are inside the long, massive ‘twilight’ cave known as the Grand Arch, through which the main road runs.  The first ‘dark’ cave to be found at Jenolan was the Lucas Cave in 1860, with its enormous caverns.  Getting into the Lucas Cave was not easy. In the early days, visitors had to actually climb over the top of the Grand Arch to get to the Lucas entrance.  Nowadays, you start inside the Grand Arch, but the tour still involves many stair steps. 

Forty years later in 1903, inside the Lucas cave, a huge branch was found, called the River Cave.  To see this astonishing underworld labyrinth, you first have to go halfway through the Lucas cave.  As you can imagine, although totally worthwhile, the River Cave tour is one of longest and most strenuous tours. 

Then in 1904, two more extensive passages were discovered, going even further into the mountain. These two caves are now known as the Orient Cave and the Temple of Baal cave.  To reach these 2 jaw-dropping caves, visitors had to go half way through the Lucas cave, down into the River Cave, further down into what we call ‘the Mud Tunnels’ and then up many stairs into either the Temple of Baal Cave or the Orient Cave.  Although ultimately extremely satisfying, it was an exhaustive struggle all the way from the Lucas Cave entrance, involving nearly 1,500 stair steps – definitely not for the faint-hearted.

After the opening of the Orient and Temple of Baal Caves in 1917, it wasn’t long before cave surveyor and pioneer of cave development, Oliver Trickett, started proposing an easier way to bring visitors in, through the opposite end.  According to his survey work, a manmade tunnel through the solid limestone could make access much easier.  

However, the idea was quite controversial, as cave experts warned that a manmade entrance would increase the airflow through the caves, drying them out, ruining cave formations and the natural environment. 

Plans for a 400-foot tunnel were finally announced in December 1953.  State Tourist Director, Mr H. E. Best, said that the tunnel was expected to cost £3,000, and was part of a £32,000 programme to develop the state’s limestone caverns and beautify their surroundings. Mr Best said that the tunnel would mean that visitors could access the Orient or Temple of Baal caves in about 4 minutes – and this would be a major improvement.” [ii]

Mr Best gave the assurance that, “Double doors, which will create an airlock, will be installed to prevent a drought entering the caverns and drying them up.” He said, “special precautions would be taken to see that the caves were not marred by tunnelling operations.” [iii]

In January, tenders were invited, and tunnel work started on 16 March 1954 and progressed by 5 feet every day. [iv]

The tunnel was not straight.  Not far from its entrance, it veers to the right and soon after, it curves again slightly to the left. After that, it straightens out.  No one seems to know exactly why it bends, but legend provides 2 explanations. One is that the contractor, Joe Lund, did it deliberately to prevent his blasting from damaging the caves towards which he was ultimately heading.

The other explanation is that the contractor had no sooner begun tunnelling when he started heading the wrong way and had to make a couple of corrections.  In 1977, Ian Driscoll (a founding member of the Sydney Speleological Society and a cave guide at Jenolan), wrote a paper about the Binoomea Cut, in which he described how “he got hold of an old world war II mine detector and modified it so that one part could be placed in the [Temple of Baal Cave] and the main instrument set up in the tunnel, thus showing the contractor the direction to bore. This idea caught on and the radio directional instrument was created” [v], and a version of it is used by speleologists today.  

So, 66 years ago, on November 19, 1954, the tunnel was officially opened by the Hon C.A. Kelly MLA, Chief Secretary and Minister for Immigration. A plaque was unveiled, acknowledging the work of the late Oliver Trickett, pioneer of limestone cave development in NSW. Speeches were made.  One story goes that to make the speeches, dignitaries stood on a makeshift dais, which unbeknownst to them, consisted of boxes filled with gelignite and covered by carpet [vi].

The final cost of the tunnel was £9,189 - more than three times the original estimate.[vii] The Blue Mountains Advertiser wrote, “Through the use of the latest drills, explosives and scientific radio direction finding equipment, the Department of Tourist Activities has been able to complete the work without any damage or disturbance to the delicate limestone formations for which the Temple and Orient Caves are famous.”[viii]

As planned, a series of airtight steel doors created air locks and maintained the existing airflow in the caves. The caves did not dry out, calcite crystal formations are now as beautiful as ever, and the cave’s natural ecosystem was preserved.

The tunnel was named the Binoomea Cut, which comes from the Gundungurra word, Binomeal, meaning ‘dark places’. [ix]

It was a huge success.  So now, when you visit Jenolan, and you explore either the Orient or Temple of Baal Caves, you enter via a long, eerie, level tunnel - a very convenient shortcut.  Once your eyes adapt to the atmospheric lighting, you can still see where holes were drilled for the blasting.  In a couple of places, where water runs in, calcite crystal is beginning to form over the grey limestone walls. 

Little by little, as the forces of nature work their slow transformation, who knows! A thousand years from now, perhaps all the walls of the manmade Binoomea Cut will be draped with sparkling white flowstone. Transparent crystal straws will hang from the ceiling and stalagmites and delicate rimpools will completely disguise the concrete floor. For now, we are grateful for the convenience of our manmade marvel - another piece of Jenolan’s quirky history.