Retaining structures or a retaining wall is any constructed wall that holds back soil a liquid or other materials where there is an abrupt change in elevation. Retaining walls have been used for thousands of years, in the construction of terraced fields on a steep slope, or a railway through a hillside, a retaining wall is used in some form or another.

Retaining structures or a retaining wall is any constructed wall that holds back soil a liquid or other materials where there is an abrupt change in elevation. Retaining walls have been used for thousands of years, in the construction of terraced fields on a steep slope, or a railway through a hillside, a retaining wall is used in some form or another.