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. fortifications (built environment)

Anotations

Scope note:

Defensive barriers of stakes, piles, or other timber and often including loopholes for gun fire, placed across entrenchments and redoubts, a harbor or river, or around a building, village, or another area in need of fortification.