Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Built Environment (hierarchy name)
4. Settlements and Landscapes (hierarchy name)
5. landscapes (environments)
6. natural landscapes
7. landforms (terrestrial)

Anotations

Scope note:

Land formations that were the site of, often having forms caused by, extinct waterfalls. For examples, a telltale horseshoe-shaped cliff may indicate that an ancient waterfall caused the form. An example is thought by many experts to exist in the Channeled Scabland of the Columbia Plateau region in eastern Washington state, formed when a huge glacial lake emptied and scoured the landscape.