All these inscriptions are identical to that carved by Artaxerxes III on the facade of the western staircase of the Tachara of Darius, proving that the present staircase of "Palace H " was constructed by this king. Yet, this staircase was not intended for "Palace H "; it was originally built for the southern part of "Palace G ", which stood north of the Hadish and east of the Tachara. Evidently, sometime after Artaxerxes III, the sculptured blocks of this staircase were removed and re-assembled in "Palace H ". Dr. A. B. Tilia and G. Tilia have shown that in place of the present northern staircase of "Palace H ", there stood a highly ornamented stairstaircase and case constructed by Artaxerxes I.
Fragments of this original these have enabled the Tilias to reconstruct the sculptured facade of the original staircase of Artaxerxes I. The original stairway of Artaxerxes I was ornamented with the representation in relief of thirty gift-bearing delegations.
They adorned the northern side of a palace which, according to a fragmentary inscription, was started by Xerxes and finished by his son, Artaxerxes I. The plan and form of this now-completelydestroyed palace are problematic. However, it is known that at least part of its western and southern edges had battlements with alternately smaller and larger crenellations, each of which was crowned with a pair of large bull horns. Furthermore, each crenellation was decorated with small "blind windows ", crosses, and arrowheads, which were carved on its outer face (looking towards the plain). The Tilias recovered fragments of a number of these crenellations from a test trench which they dug at the foot of the Terrace platform, and after restoration, they replaced them on the edges of "Palace H ". The interpretation of these horned crenellations is a matter of debate and it is not known whether they were for defensive purposes or had symbolic and religious significance. However, it is evident that this part of Persepolis was extensively re-used after the fall of the Achaemenids. Hence the Tilias maintained that this area had a particular importance which distinguished it from the other buildings on the platform. In any event, further research may shed more light on this problem.