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)
9. castles (fortifications)

Anotations

Scope note:

Fortifications consisting of a wooden or stone keep built on a mound of raised earth and a bailey, surrounded by a palisade and ditch. This type of castle was used in Northern Europe from the 10th until the end of the 13th century.