Is this the secret tunnel that we have been searching for?
Perhaps my detective skills failed and I gave up too early on the hunt for the secret tunnels, which a young Stephen Hickmott and other boys from the old Marist Brothers College used to explore in the 1960s.
But that hasn't stopped other history detectives from going on the hunt for the mysterious tunnel that led from Ye Olde Darlinghurst Gaol, beneath Burton and Liverpool streets to the Alexandra Flats on the corner of Darley Street.
Yesterday I received these sensational and intriguing photographs, which show a tunnel beneath the former jail site, now a technical college.
If you are late on the hunt for the tunnels, see the stories here and here and then come back to this post.
The student who sent me the photographs said there was an excavation contractor working at the technical college this week fixing a sewer main about 5m underground, close to the entrance on Forbes Street . . .
"As they got about 3m down they apparently started to hit the side of some very large lime and sandstone boulders,'' she writes.
"The excavation man said he noticed that they had been carved and wondered why they were so far down.
"It wasn't until later when one of the plumbers was standing in the 5m deep hole that he noticed a gap in the sandstone blocks that were now at his eye level, just big enough to fit your fist threw (above).
"The contractors must have moved one out of place with their digging machine, which then revealed a long tunnel.
"From where I was standing I could see in and I saw exactly what you described about the tunnels: 3 foot-wide limestone walls as far as the torch would shine, going off in to parts which could be those cells you were also talking about."
It certainly looks like the tunnel that Stephen Hickmott described. But until someone crawls inside them and follows them all the way, we might never know where they go.
The student has invited me to go and have a sticky beak TODAY from behind the work-fence, but I am stuck in the office and would never be able to get there.
Is there anyone who can go and have a look? Perhaps you could distract the workers somehow and then slip into the tunnel when they are not looking and just crawl for dear life.
But just imagine if they filled in the hole while you were inside and you became trapped in there forever, until you died of thirst and starvation.
I could not in good conscience encourage this kind of dangerous behaviour, but if you can go for a sticky from behind the safety of the work-fence, please do and report back with details.