TODAY is the centenary of the passing of an Act of Parliament that led to the construction via Bargo of a new line of rail between Picton and Mittagong.

On 1 December 1914, The Main Southern Railway Deviation (Picton to Mittagong) Act was assented to by the NSW Government.

Although the deviation did not open until July 1919, today's centenary is worth noting as a significant milestone. The decision had a major impact on the local landscape and on settlements in the northern localities of the Southern Highlands.

The original Picton to Mittagong section of the Main Southern Railway opened in January 1867.

From Picton this single-line track did not follow the obvious, more direct line of the Great Southern Road through Bargo that climbed up Catherine's Hill to the Southern Highlands.

Instead it was put through several miles to the west along a rocky, undulating ridge between the Bargo and Nattai Rivers.

This was the only feasible option as the more direct route would have required bridges and tunnels beyond the means of the colony at the time.

The route was described in the Sydney Morning Herald: "It may be safely said that the rocks, hills, mountains, gullies and precipitous watercourses which border the line between Picton and the Gibraltar Rock - a distance of more than 30 miles - are for the most part appalling. The country stands remote, full of rugged grandeur and unpromising desolation."

After traversing this rugged terrain, the line reached Mittagong and then proceeded through a tunnel under Mt Gibraltar to head southward across more level and fertile country, where local towns and villages took shape around railway stations at Bowral, Moss Vale, Exeter, Bundanoon and Penrose.

The line continued on through to Marulan and on to Goulburn, opening there in 1869.

From Goulburn the line was extended southward in stages.

When it reached the NSW/Victorian border at Albury in 1881, Sydney and Melbourne were at last directly linked by a rail service, although all passengers, luggage and freight bound for destinations in Victoria had to change trains there because that state's line was of a different gauge.

The NSW Southern Railway brought improved conditions of travel for passengers and provided a better freight service than had the horse-drawn carts and bullock wagons it replaced.

By the 1880s, productive grazing lands extended from Goulburn to the Riverina. Freight such as skins and hides that had previously been transported on horse and cart or bullock wagons transferred to the railway. Live sheep and cattle were hauled to the Sydney markets in railway vans.

Wheat production in southern districts had expanded significantly by the 1890s and, as exports grew, ever greater loads were carried by rail.

Because of this growth in traffic, delays became more frequent as up and down trains had to wait to pass each other on the single line.

Being the era of steam locomotives, delays also meant wastage of coal and water.

Calls began in the 1890s for the entire southern line to be duplicated but, being a huge and expensive undertaking for the NSW Railways, 20 years passed before work commenced.

In the meantime, locomotive traffic bound for Sydney from southern areas had a relatively easy run except that, beyond Mittagong, trains had to be hauled up to Colo Vale and then, after running down again, had to be hauled up to Hill Top before reaching Picton.

Even with passing loops provided at every station, the section became a bottleneck.

The introduction of assistant engines helped to handle traffic but real improvement was not achieved until 1897 when a deviation opened between Hill Top and Colo Vale.

In 1908 the line between Balmoral and Buxton was lowered and re-graded and a balloon-loop to eliminate the steep grade for up trains was inserted between Colo Vale and Braemar.

Yet the viability of the section remained problematic.

Figures later published in the Herald revealed that, during May 1912, a total of 241 down trains hauled 84,894 tons of goods, with an average load of 352 tons each.

Of these trains, 65 were worked by three engines each, 153 by two engines each, and 23 by one engine each, or a total of 524 engines to draw 241 trains.

Duplication of the existing line between Bowral and Goulburn commenced in 1913 and, the terrain being relatively level, it was completed in 1915.

For the Picton-Mittagong section, however, railway engineers recommended that it be entirely replaced with a new double-line deviation via Bargo. This was approved 100 years ago today.

To be continued

This article compiled by PHILIP MORTON is sourced from the archives of Berrima District Historical & Family History Society, Bowral Rd, Mittagong. Phone 4872 2169.

Email bdhsarchives @gmail.com.

Web: berrimadistricthistoricalsociety.org.au