After choosing Hegmatana as his capital, Diaco decided to build a huge fortified palace in the form of seven nested castles. So that the royal palace and the treasury are located inside the seventh castle.

Diaco, imitating the painting of the Babylonian palaces, ordered that the congresses of each castle be painted in a special color.

Thus: the colors of the first congresses of the castle were white, the second black, the third purple, the fourth blue, the fifth orange, and the congress of the interior fortifications was gold. The outer wall of the castle was roughly the size of the Athens wall.

The royal palace, which was erected in the last inner castle, had hundreds of rooms and people had built their homes outside of and next to these castles.

At Diaco’s request, the Medes abandoned the small towns in which they lived and came to the capital, where they built their homes around the royal castle.

After the extinction of the Medes, although Hegmataneh did not find its first center, but due to its location on the royal road, which connected Parseh (Persepolis) with Sard, was considered the summer capital of the Achaemenids and so they settled down

Herodotus considered that this city was built by Diaco and said that it had seven walls, each of the color of one of the planets.

The Iranica encyclopedia mentions the foundation of the Medes in 708 BC in the center of Hegmataneh by Diako.

In 550 BC, Ishtvigo, king of the Medes, defeats the Achaemenid Cyrus and his hegemonic supporters conquer Cyrus.

Due to Hegmataneh’s location and strategic resources, this area was probably occupied before the first millennium BC, although there is no historical and archaeological evidence in this regard.

In 330 BC, Darius III is killed and Hegmatane is conquered. Persepolis was also destroyed by Alexander the Great and the Achaemenid rule ended.