The previously-erratic output of the Scrabo sandstone quarries was transformed by the decision of John Corry ( of Concord Farm, Tullynagardy ) to lease the hill from Lord Londonderry and to start quarrying in an organised, industrial manner. He was determined to make Scrabo the source of the pre-eminement and most prestigious building stone on the island.
However by 1851 and the coming of the mainline B&CDR railway Joseph Dugan was in charge of the quarrying. Having made himself comfortable in Killynether House, he commissioned building of extensive tramway, or possibly a narrow-gauge railway, along the south face of the hill to convey stone down to a siding of the mainline. From there it could be carried to Queen's Quay for onward delivery.
Looking at a 1900 map shows what appear to be three distinct sections, perhaps having evolved gradually.
It also closed gradually; by 1922 the blue northerly section appears to have been abandoned and only one crane was listed at the southern end. By 1938 the entire system had been abandoned.
There isn't much information as to the nature of this railway, except that the last steep descent of Drum Brae to the siding was funicular and passed under the Scrabo Road near to the current house number 154.
Bing oblique image, looking west to show the line heading towards the mainline sidings.
A couple of phone photos from a passing trip.
Looking north across the grounds of house 173. A lot of clearance underway here for building of more houses. Line of the railway descent is visible.
And looking south towards the Scrabo Road is the north entrance of the underpass tunnel. Unfortunately on this occasion I didn't have the opportunity to descend and explore the tunnel itself, into which a small river now runs.