The most complete description of Siwa's Oracle Complex
among the ancient authors is that of Diodoro Siculo in the "Bibliotheca Historica, XVII 50, 1-7 written in Greek in the 50 b.C. (about)
he writes: "50,1) The land where this temple lies is surrounded by a sandy desert and waterless waste, destitute of anything good for man. The oasis is fifty furlongs in length and breadth and is watered by many fine springs, so that it is covered with all sorts of trees, especially those valued for their fruit. It has a moderate climate like our spring and, surrounded as it is by very hot regions, alone furnishes to its people a contrasting mildness of temperature.
50,2) It is said that the sanctuary was built by Danaüs the Egyptian. The land, which is sacred to the god, is occupied on the south and west by Ethiopians, and on the north by Libyans, a nomadic people, and the so‑called Nasamonians who reach on into the interior.
50,3) All the people of Ammon dwell in villages. In the midst of their country there is a fortress secured by triple walls. The innermost circuit encloses the palace of the ancient rulers; the next, the women's court, the dwellings of the children, women, and relatives, and the guardrooms of the scouts, as well as the sanctuary of the god and the sacred spring, from the waters of which offerings addressed to the god take on holiness; the outer circuit surrounds the barracks of the king's guards and the guardrooms of those who protect the person of the ruler.
50,4) Outside of the fortress at no great distance there is another temple of Ammon shaded by many large trees, and near this is the spring which is called the Spring of the Sun from its behaviour. Its waters change in temperature oddly in accordance with the times of day.
50,5) At sunrise it sends forth a warm stream, but as the day advances it grows cooler proportionally with the passage of the hours, until under the noonday heat it reaches the extreme degree of cold. Then again in the same proportion it grows warmer toward evening and as the night advances it continues to heat up until midnight when again the trend is reversed, and at daybreak once more the waters have returned to their original temperature.
50,6) The image of the god is encrusted with emeralds and other precious stones, and answers those who consult the oracle in a quite peculiar fashion. It is carried about upon a golden boat by eighty priests, and these, with the god on their shoulders, go without their own volition wherever the god directs their path.