Accuracy of Historical Records in the Qur’an

Many ancient historical anecdotes and geographical regions have been mentioned in the stories of the holy Qur'an such as : the river or sea through which the Bani Israel passed, the land of Ashab-e Hijr, Dhul Qarnayn Dam, Ashab-e Kahf's Cave, earthy paradise of Dhat al-`Imad etc., not forgetting the detailed stories of past Prophets.
The hypothesis advanced by those who see Muhammad (S) as the author of Qur’an is untenable. How could a man from being an unlettered, become the most important author, in terms of Historical literature in the whole world, and pen down historical facts with pinpoint accuracy? 
The Holy Qur’an says:

“Such are some of the stories of the unseen, which We have revealed unto you, before this neither you nor your people knew them. So persevere patiently, for the end is for those who are righteous”. (11:49).
Research on historical records in the Holy Qur’an and finding their traces is very effective in understanding the Authenticity of the Qur'an. In addition, being involved in exploring the past would provide a good background to take lessons from the past on which the holy Qur'an in the following verses to persuade us to do so:

"Have they not travelled in the earth and seen how was the end of those before them? They were stronger than these in powers..." (30:9)

"Indeed there have been examples before you; Therefore travel in the earth..." (3:136)

To appreciate the accuracy of historical records advanced in the Qur’an, few examples are cited here below, not mentioning the detailed information on past Prophets’ history:

a) Ashabe Kahf

While narrating about the duration of which ‘As-habe Kahf’ (the Sleepers of the Cave) stayed in the cave, the Qur’an says:

“So they stayed in their cave three hundred years and ADD nine...” (18:25).
The wording is quite significant. The verse does not say “three hundred and nine years” but uses the apparently cumbersome wording of “three hundred years and add nine”. Why add nine? This is because their stay was 300 years if one used the solar calendar and 309 years by the lunar calendar. The lunar year is 11 days shorter. Now 11 days times 300 years divided by 365 years is 9 years.

b) City of Iram

Another example of historical record can be found in chapter 89 of the Qur’an which mentions an ancient city called Iram:
“Have you not seen how your Lord dealt with the Aad (people), of the (city of) Iram, with lofty pillars, the like of which were not produced in (all) the land?”. (89:6-7).
Apart from its being mentioned in the Qur’an, there were no historical record about this city - Iram. The name itself was obscure even during the time of the Prophet himself, which led to a number of speculations about its possible geographical location. Some commentators of the Qur’an went to the extent of suggesting that probably Iram was the name of a hero of the Aad.
The research findings of published by the official journal of the American National Geographic society in December 1978 have conclusively shown that Iram was a city. In 1975, Dr. Paolo Mathias of the University of Rome, director of the Italian Archeological Mission in Syria ‘hit an archeological jackpot’. In the ruins of a palace apparently destroyed in the 23rd century B.C., he came upon the greatest third millennium archive ever unearthed. More than 15,000 ‘cunei form tablets’ were discovered. Among the rich details revealed by these tablets is the fact that Ebla used to have trading links with Iram....
It is inconceivable how Muhammad could describe accurately in the Qur’an the physical features and the level of architecture of a people who lived in an ancient city which was destroyed 3000 years before he was born.  

c) The body of Fir’aun

The Qur’an has explicitly recorded about what has become of the body of Fir’aun.

“This day We save therein your body so that you become a sign for those who come after you. But verily, many among mankind are heedless of our signs......” (10:92).
In this verse, the God's intention of bringing the body of Pharaoh out of water rather than leaving it decaying or being eaten by the sea animals is to give a lesson to future generations.
What is amazing that when the Qur’an was transmitted to man by the Prophet, the bodies of all the Pharaohs were in their tombs in the Necropolis of Thebes, on the opposite side of the Nile from Luxor. At the time however, absolutely nothing was known of this fact, and it was not until the end of the nineteenth century that they were discovered there.
As the Qur’an states, the body of the Pharaoh (Fir’aun) of the Exodus was in fact rescued: visitors may see him in the Royal Mummies Room of the Egyptian Museum, Cairo. How did the Prophet, who lived in Arabian desert came to know that the body of Fir’aun would be rescued for future generations to learn a lesson?