Walking Through History: A Visit to the Lapstone Hill Tunnel Open Day

The Lapstone Hill Tunnel – also known as the Old Glenbrook Tunnel – is a genuine piece of Blue Mountains railway heritage. It was built between 1891 and 1892 to bypass the original Lapstone Zig Zag, a switchback line that had been climbing the escarpment since 1867 but was proving too slow and restrictive as rail traffic grew. The tunnel runs for around 660 metres in a distinctive S-shape, following a steep 1-in-33 gradient, and opened to traffic in December 1892.

It wasn’t a great success. Without a ventilation shaft (omitted to save money, on the assumption that airflow through the tunnel would be enough), the atmosphere inside became notoriously suffocating for crews on steam locomotives labouring up the grade, and damp conditions caused rails to slip. These problems, combined with the need for a second track to handle growing traffic, led to the tunnel’s closure in 1913, when a new deviation and a second, larger tunnel took over the job just a short distance away. That newer tunnel still carries the Main Western and Blue Mountains Line today.

Since then, the old tunnel has had an unusually varied second life. During the Second World War it was reportedly used to store mustard gas, and at another point it served as a mushroom farm, taking advantage of its cool, dark, humid conditions. For decades after that it sat largely forgotten, sealed off from the public, its heritage significance recognised but its future uncertain.

What makes this year’s open days more than just a nostalgic novelty is the plan behind them. Blue Mountains City Council has undertaken significant remediation work on the tunnel in recent years, including clearing around 1,700 tonnes of waste and 1,200 tonnes of sediment, managing contamination, and cutting back overgrown vegetation. It is now pushing for the funding needed to reopen it permanently.

The vision is to turn the tunnel and its surrounding precinct into a safe, accessible public space for walking, cycling, heritage and events, providing a missing link in a safe cycling route between the Lower Blue Mountains and Western Sydney via the old Knapsack viaduct and old Bathurst road leading into Emu Plains. Proposed upgrades include drainage and remediation works, new pathway connections, lighting, accessible links, landscaping, picnic shelters, a pump track, parking and other visitor amenities.

Council has estimated it needs around $15 million to bring this vision to life and has been calling on state and federal governments to help fund it, with time pressure added by the fact that council’s lease over the tunnel is due to expire. The open days have doubled as evidence of public appetite for the project. A practical, high-turnout demonstration to government that there’s real community demand for this heritage asset to be reopened for good.

A few practical notes if you’re hoping to get along to a future open day yourself: sessions have historically been split between pedestrians and cyclists at different times, so it’s worth checking the specific timetable before you go, and cyclists are generally asked to walk their bikes through during pedestrian-only windows. Because there’s no on-site parking, allow time to walk or ride in from Glenbrook village, or even take the walk up from the base of Mitchells Pass through Knapsack Reserve on the old Great Western Highway. The first open weekend featured lots of work lights, leaving a “spooky” atmosphere in darker sections. But thanks to Blue Mountains City Council investment and remediation works, the tunnel is now “very” well lit from end to end.

Given the tunnel closes again after each open day until further funding and works are secured, keep an eye on council’s website or social channels if you want to be notified of the next opportunity. But be aware, past open days have sold out well in advance with BMCC putting up more sessions as the enthusiasm to visit this historic novelty grows.

The tunnel is a genuinely rewarding subject for photography, but it does present a few technical challenges worth planning for.

• Bring a tripod for long exposure. The tunnel is now very well lit, and so handheld photography is quite possible. But bringing a tripod allows for some extra “long exposure” fun, especially if you want to eradicate other visitors from the scene, or even captuyring the motion of walkers as they explore the tunnel.
• Try long exposure motions. Hold your camera steady in your hand, and use 3-4 second exposures as you walk forward, giving that zoom effect. Use fellow walkers in the distance to create ethereal ghost like silhouette figures
• Try a Timelapse. Placing your camera low on the tripod, setting to interval timer mode, and setting your shutter speed to 2-3 seconds gives you some great motion as people pass by in both directions. Pinned together it makes for a wonderful timelapse.
• Look for texture and detail, not just wide shots. The brickwork, water staining, and remnants of the tunnel’s various past lives (rail infrastructure, old fixtures) all make for compelling close-up shots that complement the big atmospheric “tunnel mouth” images.
• Respect the crowds and the setting. Open days can get busy, particularly during pedestrian sessions, so be considerate of other visitors when setting up shots, and avoid damage to the walls or hide holes.

Photographing the Lapstone Hill Tunnel is a rare chance to physically stand inside and capture more than 130 years of Blue Mountains history. A tunnel that was obsolete within two decades of opening, repurposed for wartime storage and mushroom farming, and is now, potentially, on the cusp of a genuinely useful third act as a community walking and cycling trail. Whether or not the funding comes through to reopen it permanently, it’s well worth making the effort to see and photograph it while these open days continue.