This follows the opening of the L2 line from Circular to Randwick in December 2019.
The L3 Kingsford Line completes the 12km CBD and South East Light Rail network, giving southeastern suburb residents a sustainable connection to the city centre.
Trams will operate on both the L2 Randwick Line and L3 Kingsford Line between 05.00 and 01.00 daily, with services every 4-8 minutes in the city centre and every 8-12 minutes in the southeast.
No more extensions are currently planned for the Sydney network, but construction of the separate $A 2.4bn ($US 1.44bn) Paramatta light rail network commenced earlier this year.
The opening comes during a state-wide decline in public transport usage, which has dropped more than 45% in recent weeks due to the coronavirus.
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