3457 years after Habuth (descent of Adam a.s from Heaven) Al-Kahf [18:94]
18:94 They said: "O Zul-qarnain! the Gog and Magog (People) do great mischief on earth: shall we then render thee tribute in order that thou mightest erect a barrier between us and them?
In the books of narrations it is described that in the heavenly scriptures like the Holy Quran and Taurat (Torah) the name of Zulqarnain was mentioned. Some believe that he was a messenger of God and according to few he was just a great king. Ibn kasir and other interpreters wrote the details of the verses in the Quran regarding Zulqarnain.
Abul kalam Azad, the cultural minister of India , in his book wrote and insisted to prove that Zulqarnain was the same Cyrus the great. But no one in the history came across the name or word which resembles Kurush or Cyrus.
The history and the narrations made Abul Kalam Azad to write a book upon this subject and described the ideology of Zulqarnain, his way of administration, and his travelling. He was born after 3457 years of habuth and the period of Kurush was before 559 Before Christ. They both were very much identical in virtues attainments, morality, customs and wisdom. They were identical but not same person.
Khizr a.s was His maternal cousin and the era of Zulqarnain coincides with the Lut a.s and Ibrahim a.s. He was well known for the secularity, organizing the governmental duties, efficiently equipped with the provisions of journey, fond of searching the spot of sunset and built the Barrier of Yajuj o Majuj.

About Zulqarnain it is written in Sur e Kahaf
Al-Kahf (The Cave18:83 AND THEY will ask thee about the Two-Horned One. Say: "I will convey unto you something by which he ought to be remembered.") 18:84 Behold, We established him securely on earth, and endowed him with [the knowledge of] the right means to achieve anything [that he might set out to achieve];
-18:86 [And he marched westwards] till, when he came to the setting of the sun, it appeared to him that it was setting in a dark, turbid sea;and nearby he found a people [given to every kind of wrongdoing]. We said: "O thou Two-Horned One! Thou mayest either cause [them] to suffer or treat them with kindness!"
18:87 He answered: "As for him who does wrong [unto others] - him shall we, in time, cause to suffer; and thereupon he shall be referred to his Sustainer, and He will cause him to suffer with unnameable suffering.
18:91 thus [We had made them, and thus he left them ; and We did encompass with Our knowledge all that he had in mind. In the Sur e Kahaf from the ayaat 82 to 98 it is written: O the Last prophet they ask you about the Zulqarnain. I will describe you its story that I bestowed Zulqarnain the kingship and every kind of facility and resource. He advanced in his journey to such extent that he reached the place where the sun sets in the evening. He observed the sun is drowning the fountain of mud, there he had a dream. I told Him: Now you can punish them or you can treat them kindly.
He replied: One who is a tyrant he will be soon punished here and after going towards God, the severe torment will be adhered to him.Those who brought faith and performed virtuously they have an excellent and deserving end. And the God Almighty grant him immense expanse in his efforts in performing good deeds.
The means and resorts of Zulqarnain were so widespread that he reached the place where the sun was rising. He came across a tribe who were ignorant of the resources to protect themselves from the heat and he made them well acquainted of their every needs. In the same manner he went forward in his way and reached a place which was between two walls there he met a tribe whom he was unaware of their language.
The people informed him: O Zulqarnain the tribes of Yajuj and Mujuj had created the turmoil and affray in our land. We will provide you the essential money and material so that you build a wall to prevent them from entering in our lands and their aggressions and violence. Zulqarnain replied: The Almighty God blessed me to such an extent that I do not need your money. You help me with man power to raise a wall between you and them.
And told them: bring the sheets of iron with the help of this we will adjoin both the mountains. Zulqarnain melted the iron sheets like red flames and with help of the water created desiring shapes then constructed a wall. The tribes of Yajuj and Majuj were unable to reach them again or breach a way in the barrier.
Zulqarnain stated: It was the blessing of God that I completed it by the wish of God. The intention of God is right and true. It is narrated by hazrat imam Sadiq a.s that Zulqarnain made a box of glass and stored food stuffs in it and tied a rope around the box and boarded on a ship. When he reached the deep waters of the sea, he seated himself in the glass box and gave the other end of the rope which was tied to the box to the captain of ship and told him: Whenever I began to shake the rope you pull me up. If did not shake it let the rope loose till I continue going deep down the sea.
For forty days he was deep in the sea. One day he saw someone is knocking the box and asking him: O Zulqarnain! Where are you Going? He replied: I want to know that how much is the depth of the sea and I want to view the kingdom of God in the sea like I observed the earth. He replied: This is the place while Nuh a.s was passing by in his ship, his axe fell down and still it did not reached the bottom of the sea. As soon as he heard it he shook the rope and they pulled him up.
Imam Sadiq a.s said: He was the slave of God and adoring the Benevolent God and doing his best in the way of God and God the Omnipotent too provided him every means and facilities. He too was inviting his people towards the One God and monotheism. He and prophet Yu’she a.s were the wise and learned men who were able to hear the words and speech of angels but they were not able to perceive them by eyes.
In another narration it is written that he became the king in the age of 12 and for thirty years he was seated on the throne of monarch as a king. He performed the hajj along with the six hundred thousand people and there he met hazrat Ibrahim khalilullah a.s and he went by walk near the prophet of God to meet him.
Ibrahim a.s asked him: How did you travelled around the world? He replied: With these nine resources:

1- سبحان من هو باق لا یفنی

2- سبحان من هو عالم لا ینسی 

3- سبحان من هو حافظ لا یسقط
4- سبحان من هو بصیر لا یرتاب

5- سبحان من هو قیوم لا ینام

6- سبحان من هو محتجب لا یری
7- سبحان من هو واسع لا یتکلف

8- سبحان من هو قائم لا یلهو

9- سبحان من هو دائم لا یسهو
 

They were four persons who ruled as kings: 1- Prophet Nuh a.s 2-Zulqarnain 3- prophet Dawood a.s 4- Prophet Sulaiman a.s. Zulqarnain army was immensely mighty, he was the great leader and he was the maternal cousin of hazrat Khizr a.s. In all his journeys he was moving along with is army and after his death his country was divided into Egypt , Greece , Syria and the West.
He was monotheist and preached the oneness of God. His grave is located in Dumatul Jandal (an ancient city of ruins located in North Western Saudi Arabia in the Al Jawf province). Zulqarnain in 2128 BC reached the west where he watched the sunset and lived there for a year and went from there to Europe and then to Siberia and made the east and west habitable and improved their living condition and appointed kings upon every country. They were the nominal kings ruling upon the people on the authority of Zulqarnain.
Hazrat Amirul mominin Ali a.s said: The place where Zulqarnain saw the sun drowning in the hot spring, it was Balqa (It is located northwest of Amman , Jordan 's capital.). He became the king after the torment of the flood in the period of Nuh a.s and lived for 200 years.

The etimology of his name Zulqarnain are as follows
1- Once he was died by a hit right on his head and again he got his life back and two horn like parts raised upon his head. So he was called Zulqarnain.
2- The design of his crown was like to horns.
3- He was able to see in the day and in the darkness of the night.
4- He lived for two centuries so he may be called“ذوالقرنین ”
5- قرن "qarn” means power, mighty and brave.
It was mentioned about the Zulqarnain in the Holy Quran as follows: I have bestowed Zulqarnain everything knowledge, power, kingdom, the means and resources, to bring into perfection the real self and the same way he followed the angel Jibril a.s.
There was a tribe who asked him: O Zulqarnain do you forgive a person who does not leave his blasphemy and punish him? He replied: Yes I will not leave him till I punish him. My torment is different from the Almighty God and the one who follows the One Omnipotent God and act righteously will get great award.
Zulqarnain reached the place of sunrise and he came across the people who were naked. It was stated by Amiral Momineen Ali a.s that the advent of Zulqarnain was after the Nuh a.s. God made him to roam and have a look around the sky and he ruled upon the kingdom of west then he occupied the east. He was well equipped with the entire resources of the progress of cultures. He was blessed with knowledge, wisdom and awareness.
In the same manner Zulqarnain continued his journey and reached a plce where the people complained him about those two tribes, the Yajuj and Majuj, Zulqarnain replied: Bring for me iron, copper water and other materials of construction. The wall of barrier was completed such that the tribes of Yajuj and Majuj could not climb it. And this wall became the source of peace for them from whom they were facing much trouble. The wall of Zulqarnain is very much popular in the history.
In the narration, it is written about an angel who got a long life. Zulqarnain asked him: What are the ways to get a longest life span? The angel replied: God had created water of life and the one who drinks it that person will be alive for ever.
He asked: Where I could find that spring of water? He replied: It is in the darkness ‘Zulmath’ He asked: Where is the darkness? He replied: It is in the east and on the earth. And the angel disappeared. Zulqarnain gathered all the wise men, scholars and learned people of the society and told them to find out the place where the water of life exists. He conducted a meeting and said: O the wise and fully aware people, do you know from the books of the past prophets, informations of the past and from the other scholars that where is the spring of life?
Many discussions on this subject were carried on and the negative and positive answers were approaching all over. A young man was sitting in a corner and he was not uttering a single word who was the son of a successor of a prophet. And meanwhile Zulqarnain was not able to take out any result out of their discussions.
He asked that young man: Do you have any clue about the matter? He replied: O king of knowledge I am aware of this subject. King Zulqarnain got delighted and came down his throne and made the young man to sit beside him and treated him with much kindness and interest and he paid keen attention towards the young man to hear what he was going to say.
The young man said: I have read some chapters from the scripture of the Adam a.s which was descended from the heaven; the subject of your interest is mentioned in that scripture.

3457 years after Habuth (descent of Adam a.s from Heaven)
A young man was sitting in a corner and he was not uttering a single word. He was the son of the successor of a prophet. And Zulqarnain was not able to take out any result out of the discussions of the scholars who were gathered over there.
He asked that young man: Do you have any clue about the matter? He replied: O king of knowledge I am aware of this subject. The king Zulqarnain got delighted and came down his throne and made the young man to sit beside him and treated him with much kindness and he paid a lot of attention towards the young man to hear him what he was going to say.
The young man said: I had read some chapters from the scripture of the Adam a.s which were descended from the Heaven and the subject of your interest is mentioned in it. The day prophet Adam a.s was taught the names, Asmaاسماء%%%(he was made aware all the names and addresses of the springs and trees and they were written in the scripture and conveyed to hazrat Adam a.s.
I have read in that scripture a spring is created in the earth and it is called Ainal Hayatعین الحیاتspring of life. It is the will of God that anyone who drinks the water from the spring of life he will be immortal and alive for ever. And that spring is in the Zulmathظلماتdarkness where neither the Human nor the Jin is allowed to enter. Zulqarnain enquired: O young man! where is the Zulmath and the spring of life, can you tell me?
The young man replied: Yes I have read in the book that it is towards the lands of east.
Zulqarnain felt extremely happy and ordered all the wise men, learned, nobles and religious jurisprudence to assemble in his court, their number reached to thousand. He commanded all of them to get prepared for a journey and provide all the means and facilities of the travelling. Their journey moved towards the spot of sunrise and passed the oceans, deserts and mountains. They were unaware of the earth’s sphere, the solar system and the movement of the earth. They travelled for 12 years and reached the beginning of the darkness “Zulmath”.
According to the information received the darkness of Ainul Hayat(The spring of life ) was not like the darkness of the night and the day nor like the darkness of horizon.
He stayed near the Zulmath with his army and called the learned and wise people to visit him there and said: O the wise people of my nation! I want to reach the spring of life with all my efforts. They revered him and said: You are performing such a task that no one dared to do it before and after you, we do not know who will have the courage to do it again. The aim which you have chosen, till date no prophet and messenger even crossed that passage. Indeed not a king or a leader thought to step into that way.
Zulqarnain expressed: I have no alternative way beside this ambition. They replied: We have a strong believe that if we reach the Zulmath you will obtain your wish without any effort. But we are afraid that you may get harm and it may cause your death.
In the commencement of the journey he said: O wise men advise me, which of the animals have most clear and sharp eye sight. They informed him: The virgin mare (female horse) had such an eye sight. By the command of Zulqarnain 6000 virgin mares were brought to them and he selected 6000 wise and learned among them and each one of them was given a mare to ride. Hazrat Khizr was appointed to lead the army of 2000 persons and assigned him on the front position of army as a leader.
He commanded the Khizr a.s and his army to enter the Zulmath ‘darkness’ and then he himself leading the army of 4000 marched into the Zulmath. He beforehand expressed his last wish: If I am lost in the Zulmath and if the companions are not able to see each other then they have to wait 12 years for me there and if it takes more than that period they can return back to their home land.
Khizr a.s who his maternal cousin requested: O king we are entering in the Zulmath “darkness” and could not see each other there, if we lost then how can we search each other.
Zulqarnain gave him a red grain, its light was like the flame of a candle and said: Whenever you lost each other, throw this grain on the ground it will get bright and all of you gather there.
Khizr a.s took hold that red grain and they entered the darkness. In the process of their movement in the Zulmath, The spot where Khizr a.s was loading his luggage on the horses for proceeding forward, on that same junction Zulqarnain and his army were alighting from their horses for relaxation.
In the zulmath khizr reached a river and told his companions: Halt here and do not move.
Khizr a.s dismounted from the horse and he threw the red grain in the water. When the grain was sinking in the water it did not gave a single sound and vibration in the water. Khizr a.s felt bewildered and did not utter a word; he thought that may be the grain was lost.
When the grain reached the water bed it gave a sound and a bright light sparked out of it. When Khizr a.s followed the light he viewed a spring which was whiter than milk and sweeter than honey and he drank that water and took a bath in the spring. Then wore his dress and picked up the red grain of light from the water and threw it towards his companions and a sound was heard out of it, all of them followed it and Khizr proceeded in his journey along with his army.
Zulqarnain after Khizr reached the same spot but he did not got aware and acknowledged about the spring he proceeded ahead in his journey, day and night and reached the brightness and luminance of the sky.
That light was neither like the radiation of the day or the sun nor like the luminosity in the night. It was a light from the brightness of the God. Then they reached a desert of red ground with very soft sands. Its pebbles were pearls suddenly he came across a castle, its length was 3 miles. Zulqarnain alighted with his army on the gate of the castle and he himself alone entered the mansion; there he observed an iron cage which was of a considerable length and strangely arranged on the both sides of the citadel.
A black bird was perched there as if it was between the sky and the earth and it seemed like a stone. When Zulqarnain went near, the bird inquired: Who are you?
He replied I am Zulqarnain. The bird expressed: Does that earth with its entire expanse and blessings was not enough that you passed the darkness “Zulmath” and entered into my castle.
These words created fear and dismay in the heart of Zulqarnain and he heard a voice: Do not fear and reply the questions. He said: Ask me. The voice interrogated him about the immoralities such as giving false witness, concealing the truth and forgetting the Oneness of God. Then the bird placed a ladder and guided him towards the lights there he sighted the mysteries. Both of them discussed a great deal. Zulqarnain was gifted a stone and he accepted it and returned back.
He met Khizr a.s and conversed with him on various matters and on the qualities of man. Zulqarnain got disappointed for not getting the water of life he argued about the misfortunes of the world, sorrows of man and the hardships and cried deep heartedly and abandoned the desire to acquire the water of life. Both of them returned back and on their way they heard the sound of the horse galloping and asked: What is that? Zulqarnain replied: All of you gather some of the sands.
Some said: What is the use to take the sands with us? A few of them collected handful of sands.
Zulqarnain stated: One who does not takes it will be regretful and those who picked them up will be remorseful too. When they came out of the Zulmath “darkness” they realised that all the sands were the precious jewels.
Zulqarnain with all his companions went to the Dumat Al-Jandal and lived there until his death.