they are called dykes.
The motte is the the mound of earth the castle was built on.
Earth miterial
The Mound Builders built mounds of earth and stone
They were known for their agriculture, art and mound building of ceremonial and burial sites.
hill
which civilization built the great mound.
Because they built large mounds for ceremonial and burial use.
Mound Builders
A Motte is a man made mound of earth in which a Norman tower or a dungeon is built on.
embankment is; a long mound of earth or store, sometimes built to raise a roadway.
Mound builder societies were characterized by their construction of large earthen mounds used for burial, religious, and ceremonial purposes. They were often organized into complex social and political structures, with some societies being chiefdoms or quasi-states. These societies flourished in different regions of North America, such as the Southeast, Midwest, and Great Plains.
The Adena Mound