According to Muhammadan & Arab tradition (Post Islamic), this was the well that supplied water to Hagar and Ishmael.

Genesis 21:" 14. And Abraham rose up early in the morning, and took bread, and a bottle of water, and gave it to Hagar, putting it on her shoulder, and the child, and sent her away; and she departed, and wandered in the wilderness of Beersheba.

         15. And the water was spent in the bottle, and she cast the child under one of the shrubs.16. And she went, and sat down opposite him a good way off, as it were a bowshot; for she said, Let me not see the death of the child. And she sat opposite him, and lifted up her voice, and wept.17. And God heard the voice of the lad; and the angel of God called to Hagar from heaven, and said to her, What ails you, Hagar? fear not; for God has heard the voice of the lad where he is.18. Arise, lift up the lad, and hold him in your hand; for I will make him a great nation.

         19. And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad to drink.20. And God was with the lad; and he grew, and lived in the wilderness, and became an archer.

        21. And he lived in the wilderness of Paran; and his mother took for him a wife from the land of Egypt"

       In the original Biblical story above, there is no mention of Arabia or Mecca since both Hagar and Ishmael remained in the vicinity of Beersheba and Egypt.

       The well that was revealed by Gabriel was near Beersheba and NOT Mecca and had no name especially NOT ZAMZAM.

       Most important of all, Hagar took him to EGYPT and NOT ARABIA.

       Setting aside the fact that the story as depicted in the Quran and Ahadith contradicts everything that the Bible narrates about Abraham, Ishmael and Hagar, it is important to point out that in the parched environment of the Arabian peninsula, all sources of water especially wells were venerated; Zamzam was allegedly a holy place among the Arabs of the Jahiliah (long before Muhammad and his Quran).

       Anyway, it was BECAUSE of Zamzam, that an enclosure surrounding it was built to protect it and then the Ka'ba became  a HOLY place, venerated by the pagan Arabs.

       The allegations made by Arab historians and scholars that Zamzam was holy to the pagan Arabs - because they already knew about Hagar and Ishmael- are totally  FALSE and cannot unsubstantiated by any records.

        There is not to be found a single written or oral tradition anywhere in Arabian 'history or literature' to support such a preposterous statement. Moreover, from both the logical and practical points of view, the well of Zamzam which is in the vicinity of Mecca, is almost one thousand miles away from Beersheba and, neither Hagar and Ishmael nor  even a camel could have survived this distance on one bottle of water.

        In fact, as a matter of logic and historicity, one should ask:
If they were so important and holy, why then does the Quran NEVER mention the names of either Zamzam or Hagar implicitly or explicitly?

       The Muhammadan version of the Ishmael & Hagar story was copied - and suitably altered and embellished to fit the Arabian psyche - from the Midrash version as clearly demonstrated in (Ginsberg's Legends of the Jews Vol.I, p:265).

       In the Hebrew version, the well was called Miriam's well created in the twilight of the sixth day of creation.

        It was an extremely practical and clever policy by the 'Muslim' scholars to associate many Arab pagan 'traditions' with the Biblical stories of Abraham, Ishmael and others and in this manner perpetuating the MYTH and PREPOSTEROUS LIES that the Jahilyah 'traditions' were cognizant of previous revelations - contrary to what the Quran itself asserts as otherwise - through the process of 'Islamizing' them.

       In the Qarawiyun Manuscript (folio 43a-b), there is a completely DIFFERENT version by (Ibn Kathir's Sirah: pp 117f; Zamzam) from both the Bible and Ibn Ishaq in the recension of Ibn Hisham's 'Sirat Rassool- Allah':

       " Then Gabriel came to the prophet when prayer had been ordained and he hollowed a place in the wadi with his heel so that a spring of running water (I. K. Zamzam) gushed forth. Gabriel performed his ablution while Muhammad watched him. He washed his face, rinsed his mouth, sniffed water up his nostrils, and wiped his head and his ears and his legs as far as the ankles, and sprinkled his pudenda. Then he arose and prayed two bowings and prostrated himself four times upon his face.

       Then the prophet returned, Allah having refreshed him, and his mind was at rest, for what he yearned for had come to him from Allah. He took Khadija by the hand and brought her to the spring and performed his ablution as Gabriel had done. Then he made two bowings and four prostrations, both he and Khadija. Thereafter the pair of them used to pray secretly"

       If this is the case, then it completely negates the possibility that Zamzam was as old as the days of Ishmael and the stories are rendered totally incompatible and suspect, especially since Zamzam was allegedly a venerated well in Mecca long before Muhammad.

       Another tradition as related in Ibn Ishaq's Sirat (A. Guillaume; p 45), that it was Abd al Muttalib who was ordered to re-dig up the well of Zamzam - which was a depression between the two idols of Quraysh, Isaf and Na'ila - in a vision that he received. It is within the Ka'ba enclosure and near the statue of Hubal, the most powerful of all the stone gods. In the alleged later invented tradition about the pagan Arabs, it is near Maqam Ibrahim (A. Guillaume; p66).

Sahih Al-Bukhari HadithHadith 3.556        Narrated byIbn Abbas
The Prophet said, "May Allah be merciful to the mother of Ishmael! If she had left the water of Zam-Zam (fountain) as it was, (without constructing a basin for keeping the water), (or said, "If she had not taken handfuls of its water"), it would have been a flowing stream. Jurhum (an Arab tribe) came and asked her, 'May we settle at your dwelling?' She said, 'Yes, but you have no right to possess the water.' They agreed."

       *** This tradition shows that the Jurhum were Arab tribes BEFORE the alleged arrival of Ishmael the Hebrew to the valley of Mecca.

       Hence the descendants of Ishmael, from whom came Muhammad, were not the original Arabs of the Hijaz but Arabised Arabs (Musta'riba) ***

HadithHadith 4.582        Narrated byIbn Abbas
The Prophet said, "May Allah bestow His Mercy on the mother of Ishmael! Had she not hastened (to fill her water-skin with water from the Zam-zam well), Zam-zam would have been a stream flowing on the surface of the earth." Ibn 'Abbas further added, "(The Prophet) Abraham brought Ishmael and his mother (to Mecca) and she was suckling Ishmael and she had a water-skin with her."

       *** it is to be noted that  one of the allegedly most important women in the Muhammadan tradition, the mother of Ishmael, Hajjar/Hagar, is NEVER mentioned by name neither in the Quran nor in many of the Hadiths, such as above as she is referred to only as 'the mother of Ishmael' ***

Fiqh-us-Sunnah   Fiqh 5.82
The Origin of Zamzam Well
Explaining the origin of Zamzam Ibn 'Abbas said: "When Hajar reached the (mountain) of Marwah in search of water for her baby son Isma'il and herself to quench their thirst. she heard a sound, and said to herself, "Quiet." She again heard the sound, whereupon she said, "I have heard you. Help me, if you can." All of a sudden she found an angel at the place where now Zamzam is. He either dug it with his heel or touched it (the ground) with his wing and a spring of water appeared. Hajar encircled the water with soil. She took some water in a container she had, and water kept bubbling up unchecked."
Ibn 'Abbas reported that the Prophet (peace be upon him) said, "'May Allah shower His mercy on Isma'il's mother. Had she left it untouched, or (the narrator is not sure) the Prophet said, had she not drunk of its water, the Zamzam would have turned into a clearflowing spring.' He added, 'So she drank the water and gave some to her son.' The angel said to her, 'Fear no loss, because this is the site of Allah's House, which this boy and his father shall build. Allah never permits His servant to be lost. At the site of the House was a hill that was split by flood waters running down its right and left."'

       *** The alleged tradition of the pagan Arabs contradicts in every step the details as given in the original version of the story in the Bible.

       The Biblical record mentions that Ishmael was over 14 years old when Abraham sent him and his mother away from Beersheba. He definitely was not a BABY.

       In conclusion, it is not difficult to separate FACT from FICTION since any reader has the ORIGINAL story in the BIBLE which was REVEALED to Moses 2200 YEARS BEFORE Muhammad and the myths and legends created by himself and his followers to PERVERT, CONTORT and TWIST, History, Facts, Religion and VERACITY ***