H undreds of rail enthusiasts and a handful of bewildered commuters have ridden the first service on a long-awaited extension to Sydney’s metro line, bringing an end to more than two years of replacement buses.

The 4.31am train on the south-west metro extension left Bankstown on time on Friday, arriving at Sydenham, where the line previously terminated, just over 20 minutes later. It carried on to Tallawong in the city’s north-west at the end of what is now a 66km continuous, high-speed, driverless line.

Early at Bankstown, hundreds of rail enthusiasts were already queueing for a spot on the first service an hour before it departed.…