Construction of workshops on the site began in about 1904, when a locomotive depot was built by the East Greta Coal Mining Company.
This was a two road engine shed, and was replaced in 1912 by a wooden framed twin gable four track galvanised iron shed constructed nearby.
In 1981 this was in turn demolished to make way for a modern steel portal framed locomotive shed of slightly shorter length than the original timber shed.
The present workshop was constructed some time between 1912 and 1918.

 On the site by 1918 were also a sand drying shed, a signing-on cabin and a wooden coaling platform.
An elevated coal loader fed via conveyor was built in 1927.
Goods sheds from Caledonia and Weston Stations were moved to the site in 1930 to serve as an oil store and a lunch room.
A brick bath house was built in 1943.
In 1957 a toilet block, a machine shop and stores building, and a new signing-on cabin were built.
The old battery store was demolished.
In 1981 a new sand house and battery shed were built.

The original Mount Dee homestead on top of the hill became offices, and the first new building was the large Erecting & Repair Workshop.
As operations expanded in the 1920s most of the infrastructure was established, with brick buildings added in the 1950s and the last replacement steel framed Running Shed built in 1981.
Construction of workshops on the site began in about 1904, when a locomotive depot was built by the East Greta Coal Mining Company. This was a two road engine shed, and was replaced in 1912 by a wooden framed twin gable four track galvanised iron shed constructed nearby. In 1981 this was in turn demolished to make way for a modern steel portal framed locomotive shed of slightly shorter length than the original timber shed. The present workshop was constructed some time between 1912 and 1918. 
 On the site by 1918 were also a sand drying shed, a signing-on cabin and a wooden coaling platform. An elevated coal loader fed via conveyor was built in 1927. Goods sheds from Caledonia and Weston Stations were moved to the site in 1930 to serve as an oil store and a lunch room. A brick bath house was built in 1943. In 1957 a toilet block, a machine shop and stores building, and a new signing-on cabin were built. The old battery store was demolished. In 1981 a new sand house and battery shed were built.
The original Mount Dee homestead on top of the hill became offices, and the first new building was the large Erecting & Repair Workshop. As operations expanded in the 1920s most of the infrastructure was established, with brick buildings added in the 1950s and the last replacement steel framed Running Shed built in 1981.
South Maitland Railway Workshops