All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Narrated Ibn `Abbas:
…………………………………..When the water in the water-skin had all been used up, she became thirsty and her child also became thirsty. She started looking at him (i.e. Ishmael) tossing in agony; She left him, for she could not endure looking at him, and found that the mountain of Safa was the nearest mountain to her on that land. She stood on it and started looking at the valley keenly so that she might see somebody, but she could not see anybody. Then she descended from Safa and when she reached the valley, she tucked up her robe and ran in the valley like a person in distress and trouble, till she crossed the valley and reached the Marwa mountain where she stood and started looking, expecting to see somebody, but she could not see anybody……………………………………………………………..." {Related by Bukhari}.
According to this Hadith, As-Safa and Al-Marwa are mountains and the mother of Ismail walked back and forth in the valley between them, which is, now, the place where people walk back and forth to perform Saa`i. If we imagine the peak of As-Safa and the beginning of the place from which people walk back and forth-which represents the whole extension of the mountain from this side-then the peak of As-Safa and place of the Zamzam well-which is the extension of this mountain from the other side-and we look a third time to the top of As-Safa and the end of the moumtain`s foot from the third side (other than the side where the palaces are built), we realize that the extension of the mountain (Safa) from the fourth side isn`t limited to the area where people performed Saa`i. Similarly, this applies to Al-Marwa Mountain noticing its peak and the distance separating it from the area where people walk back and forth and from the well of Zamzam.
People have allocated an area for performing Saa`i between the safa and the Marwa as needed. Similarly, they stayed Arafat, as needed, although mount Arafat is vast.
Based on this, we conclude that if the expansion lies within the width of both mountains (As-Safa & Al-Marwa), then the Saa`i is valid; if not , then the Saa`i is invalid.
The final say regarding the extension of both mountains is that of the geologists and one of them told me (Late Mufti Nooh Qhodat) that there are modern equipment that can give the exact extensions of any mountain, so it is better to resort to these specialists.
Undoubtedly, the expansion of Al-Haramain and pilgrimage sites have facilitated for the performers of Haj and Omrah and those in charge of this will be rewarded by Allah. In addition, the growing number of pilgrims (The guests of Allah, the Most Merciful) due to the convenience of the means of transport should be accompanied by providing means of comfort, of course, in line with the rules of Islamic Sharia. And Allah The Almighty Knows Best.