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. transportation structures
9. [transportation structures by form]
10. bridges (built works)
11. [bridges by form]

Narrower term/s

• drawbridges
• bascule bridges
• lift bridges
• swing bridges
• transporter bridges

Anotations

Scope note:

Bridges with one or more spans that are lifted, raised, turned, or slid from their normal position to allow passage of navigation. Examples are vertical-lift bridges, drawbridges, transporter bridges, and swing or pivot bridges.