Sydney's city circle train stations are out of action as maintenance teams re-rail the tracks between Central and Redfern.
Key stations including Central and Town Hall are closed. Buses are also replacing the inner west line to and from Ashfield.
Sydney Trains Director Operations, Tony Eid said the organisation had provided extra public transport replacement services to events such as the Spring Racing Carnival and the One Day International cricket match.
"We are committed to providing a safer and more reliable network and thank customers for their patience while we carry out these upgrades," Mr Eid said.
Maintenance teams will also be updating the wiring, signal and drainage systems at Redfern station.
The track work will continue until 2am on Monday when normal train service will return.
