Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Built Environment (hierarchy name)
4. Single Built Works (hierarchy name)
5. single built works (built environment)
6. [single built works by specific type]
7. [single built works by function]
8. industrial structures
9. mine structures

Anotations

Scope note:

Structures made of steel, reinforced concrete or wood which stand at the entrance of a mine shaft and support pit-head gear from the shaft, at the top of which two wheels guide cables off to a winding engine.