Until 1874, the gateposts stood at the foot of the west capitol grounds, but in that year were moved to their present locations. The gateposts are sand stone pillars measuring 5' x 5' at the base and approximately 12' in height.
The design of the gateposts is classical. Horizontal bands, around the top of the pillars, are carved out of the posts and they are topped with a frieze relief matching the one atop the gatehouses. The design atop the posts is again a classical motif, volutes using the stylized acanthus leaf form.
The two gatehouses differ in that the columns surrounding the doorway of the structure at 15th Street and Constitution Avenue rise directly out of the pavement whereas the columns on the other structure are set on cement block supports. The 15th Street and Constitution Avenue Gatehouse also uses only six horizontal bands at the corners, while the other gatehouse uses seven. The 17th Street gatehouse rests on a cobbled brick foundation with the 15th Street gatehouse resting on a cement foundation