PM rides the New York subway

For a man who loves trains, how else is there to get around New York other than catching the subway?

That's just what Malcolm Turnbull and wife Lucy did after visiting the 9/11 memorial and museum during their first stop in the Big Apple on Saturday.

The pair chose to hop on at Fulton Street station with Mr Turnbull remarking on the underground marble walls of the platform.

It was a short ride for the pair of just two stops - skipping Wall Street for Bowling Green station - before joining locals in climbing the stairs to a sunny Battery Park.

"I'm a great fan of subways generally," he later told reporters in the park.

"I've travelled on the New York subway many times."

Mr Turnbull said Fulton Street is one of the oldest stations with lots of iron columns.

He conceded to being much more interested in public transport than many other people.

"But it is the key, you can see actually in this city how important a good metro system is."