The engine, which can be found on the Iron Mountain walking trail, is one of the many structural remains that once formed the complex network of operations in this area.
The property is the former home of the Fitzwilliam coal mining family but had fallen into a state of structural disrepair, partly because of the number of mining shafts in the area.
Structural criticisms aside, a building that squeezed millions of square feet of office space into a 16-acre area was not made for its inhabitants, Darton said.