The splitting of the moon is mentioned in the Holy Qur'an, Surah Al-Qamar (54), Verses 1-3:

The hour drew nigh and the moon was rent in twain. And if they behold a portent they turn away and say: Prolonged illusion. They denied (the Truth) and followed their own lusts. Yet everything will come to a decision.
 

The idolaters in Mecca used to persecute the prophet and torture him, seeing that their attempts did not bring any fruit, they began to ask for miracles , they asked him to split the moon.
 

The prophet, who was keen on imparting Allah's message and winning them to the fold of Islam, prayed to Allah to split the moon hoping that they would embrace Islam.
 

Having finished his prayer to Allah, he pointed to the moon with  his index finger and the moon, to their mortification, was  split into two halves and kept separating till each of the two halves was seen on the two nearby mountains. The idolaters, having seeing the miracle, expressed their anger saying

"This is the work magic; you have spelled magic on us."
 

Abu-Jahal, the archenemy of the prophet, said

" If this is not magic, people coming to us from a far distance won't be affected by this magic. If they say that they didn't see the moon being split, then he will be surely a magician."
 

A few months passed and merchant caravans began to reach Mekka, each was asked if they had seen the moon" split, and they all emphasized that they saw the moon on a certain day split."

Historical evidence

Chakrawati Farmas, King of Malabar in India, WITNESSED the splitting of the moon.

The incident relating to King Chakrawati Farmas is documented in an old manuscript in the Indian Office Library, London, which has reference number:, 2807, 152-173. It is quoted in the book “Muhammad Rasulullah,” by M. Hamidullah: “There is a very old tradition in Malabar, South-West Coast of India, that Chakrawati Farmas, one of their kings, had observed the splitting of the moon, the celebrated miracle of the Holy Prophet (pbuh) at Mecca, and learning on inquiry that there was a prediction of the coming of a Messenger of God from Arabia, he appointed his son as regent and set out to meet him. He embraced Islam at the hand of the Prophet, and when returning home, at the direction of the Prophet, died at the port of Zafar, Yemen, where the tomb of the “Indian king” was piously visited for many centuries.”

In one of Dr. Zaghlool Al-Najaar’s seminars  in one of the British universities he said:

"The miracle of the splitting of the moon has been proven recently”… “One of the British brothers who is very concerned about the state of Islam "Dawood Musa" who is the new chairman of the British Muslims party who is planning to enter the coming elections under the banner of Islam, which is spreading extremely fast in the west said “
 

Dr Zagloul Al—Nagar in a TV programme explain how an English politician, Dawood Musa, converted to Islam. He says:

While he was searching for the true religion, a friend gave him a copy of the Quran translated in English. He opened it and came across Surah Al-Qamar and read: "The hour has come and the moon has split”
 

He couldn't believe what the verse says, so he stopped reading the Holy Quran. Then one day while watching a program on the BBC, The broadcaster was talking to three American space scientists, and the broadcaster was criticizing spending so much money on space projects while thousands of people die daily of hunger.
 

Unconcerned of the amount of money spent on the space projects, the space scientists referred to another project on which 100 billion dollars was spent. The broadcaster cynically commented: "So much money to put the American flag on the moon!  "
 

The scientists stated that this much money was spent because they were trying to study the internal structure of the moon to determine the similarities it has with the Earth, and they said that they were surprised to find a ‘Belt of Rocks’ that goes from the surface of the moon right to the inner depths.


Being surprised, they gave this information to the geologists, who were also surprised, as they concluded that this mean that the moon was once split into two parts and then was reunited again."  Watching this brother Dawood Musa jumped off his seat screaming “This is Muhammad’s miracle which occurred more than 1400 years ago, and now the Americans are spending billions of dollars to prove it to the Muslims. He then said “This must surely be a true religion."