More than 100 massive Super-T beams were installed 25 metres underground at Barangaroo Station.
Weighing 34 tonnes each, they were lifted into the station box using a 90-metre-high tower crane.
The beams, installed earlier this year, form the roof of the underground concourse.
Construction of the crossover cavern at Barangaroo is also now complete. The crossover cavern will allow trains to change tracks.
Note: these images were taken in April 2021, prior to current COVID-safe guidelines for construction sites