Thousands of Sydney rail travellers are expected to board the new driverless northwest Metro network, which opens today.

The $7.3 billion project has taken five years to complete and is expected to lead to faster commuting times.

It's the first driverless service in Australia.

The line will run trains every four minutes during peak hour from Rouse Hill in the city’s north west to Chatswood, stopping at 13 stations once it reaches full operation.

The $7.3 billion project has taken five years to complete. (Nine)

Passengers can expect travel-friendly new features on the new trains. (Nine)

The free opening today is expected to draw thousands of Sydneysiders.

Rail chiefs say passengers can expect new features. Not only are the trains driverless, but the train sits flush with the platform, making boarding easier for wheelchair passengers and parents with prams.

And there are no enclosed carriages, enabling travellers to see from one end of the train right down to the other end.