In classical architectural orders, the trabeation is a horizontal structure that includes the architrave, frieze and cornice and rests on vertical supports such as columns or pillars.
The architrave, which rests on the capitals of the columns, has the structural function of supporting the parts above; the frieze, superimposed on the architrave, has ornamental value; the cornice, superimposed on the frieze, has the function of crowning and protecting the parts below.