The Cockatoo Run is a railway journey run by an organisation known as 3801 Limited. 3801 is a steam engine owned and operated by the organisation, of the last, largest and most powerful type used in New South Wales. It is a magnificent monster. At this point, therefore, lest any misunderstanding arise, it should be made clear that 3801 is not the engine used on this trip. The Cockatoo Run is operated by an elderly diesel locomotive.
The journey thus far is a pretty one, but it can, in fact, be travelled by a double-decker CityRail train offering an even better view. Now, however, the train branches off the main line and runs on a single-track line leading up the Illawarra escarpment to Robertson and Moss Vale.
This was originally constructed to take pressure off the main line and to allow heavy trains travelling to the industrial areas around Wollongong and Port Kembla to avoid passing through the Sydney suburbs.
The problem with it is that it is very steep. The line rises some 600 metres in sixteen kilometres, a long, long climb at an average gradient of 1 in 27, so it is little used nowadays. The climb up the escarpment is a scenic one and the views are very good, with the train making one stop for photographs.
As mentioned above, there are CityRail trains to Thirroul which offer a better view and are much cheaper. The train reaches Robertson at which point the climb ends and it is a flat run to Moss Vale. Passengers have the option of alighting at Robertson and going on a bus tour of the area, including a lavender farm, or continuing to Moss Vale without the benefit of the tour. The tour, if taken, is included in the fare. Another option is to have lunch on the train as it climbs the escarpment.