Audley Boatshed is located just 3km off the Princes Highway. Just turn off the Princes Highway, between Sutherland and Engadine, into Farnell Ave (look for the National Park and Historic Boatshed signs on the Highway).
Alternatively you can catch a train to Loftus and ride the tram from the Tramway Museum into the Royal National Park on Wednesdays, Sundays and school holidays.