Location of Takht-e-Jamshid

The uneven plan of the foundation of the terrace acted like a castle whose angled walls enabled its defenders to target any section of the external front. Diodorus writes that Persepolis had three walls with ramparts, which all had towers to provide protection space for the defence personnel. The first wall was 7 metres tall, the second, 14 metres and the third wall, which covered all four sides, was 27 metres in height, though no presence of the wall exists in modern times