Sydney’s largest metro construction program has marked a symbolic milestone, with the final tunnel boring machines (TBMs) completing their work and beginning their journey off site.

After carving out tens of kilometres of underground tunnels beneath the city, the last of Sydney Metro’s TBMs have been carefully dismantled and transported by road, signalling the conclusion of the project’s main tunnelling phase. Their departure closes a chapter that has been central to delivering the extensive underground network now taking shape.

Over several years, the TBMs excavated tunnels beneath densely built‑up areas, waterways and transport corridors, operating around the clock to create the foundations for future metro trains. Each machine weighed hundreds of tonnes and was custom‑assembled underground before beginning its drive, advancing metre by metre through varied ground conditions.

With tunnelling complete, the project’s focus has shifted firmly to fit‑out and systems work. Electrical, signalling, communications and station infrastructure are now being installed within the finished tunnels, alongside testing and commissioning activities that will ultimately allow trains to begin operating safely.

The removal of the final TBMs required a complex logistics operation. Components were lifted, loaded and transported in stages, with careful planning to minimise disruption to surrounding communities. For project teams, the moment represents both a technical achievement and a visible sign of progress toward opening day.

Once operational, the expanded Sydney Metro network will deliver faster, more frequent services, increased capacity and fully automated trains across key corridors. The completion of tunnelling removes one of the highest‑risk and most technically demanding phases of construction, providing increased certainty around delivery timelines.

While much work remains above and below ground, the farewell to the tunnel boring machines marks a major milestone in transforming Sydney’s rail network and bringing the next generation of metro services closer to reality.

Source: Sydney Metro