In a "religion" which was founded upon centuries of idolatry, probably no physical objects are as holy to the followers of Muhammad than the Kaaba, a granite structure standing inside the Grand Mosque in Mecca, Saudi Arabia, and the mysterious "black stone" which it contains. These objects did not originate with Muhammad, of course, because Muhammad originated very little: rather, he co-opted them for his new "faith," just as he plagiarized the Old and New Testaments to create the Koran. Like most false prophets, he was an inveterate thief and liar who lacked the imagination to actually "create" anything, unless it was religious sanction for murder, pedophilia, and the subjugation of women.
So important is the Kaaba, and its "black stone," that visiting Mecca to adore it, at least once in one's lifetime, is considered one of the Five Sacred Duties of Islam, to be performed by every Muslim. Pilgrims visit Mecca year-round, but the most important time is during the yearly Hajj, when literally millions of Mohammedans descend upon Mecca at once. This year's Hajj will fall between October 13 - 18.
The following video gives the factual historical data behind the Muslim superstitions surrounding the Kaaba. However, it omits one rather delicate, and disgusting, detail.
The "black stone" itself has been claimed, from earliest antiquity, to be a fractured meteorite, a "sign from the heavens" of Allah's presence (even before the term "Allah" was used). Some Muslims, and some very stupid Christians, have associated the shattered stone with the "image which fell down from Jupiter" referenced in Acts 19:35 (which may have been an actual object, or merely a superstition; the Bible doesn't say, but the context tends to indicate the latter interpretation). This is nonsense. It's probably not part of a meteorite at all; although Muslims have forbidden any inspection of the stone since the 19th Century (rather like the Roman Catholic Church restricts access to its "original text of the Bible," Textus Vaticanus), scientists who inspected the rock posited that it was lava, basalt, or some other form of igneous rock.
What is more interesting is the manner of display chosen for the fragments that make up the black stone. Muhammed himself is credited with fitting the pieces into the silver setting in which it now appears .... which, according to people from virtually every background, deliberately resembles a woman's vulva. This is precisely what we would expect from a "prophet" and a "religion" that is obsessed with sex. Hindu scholars in particular (who claim that the Kaaba was originally a shrine to a Hindu goddess) are quite adamant on this point, as they believe it shows that Muhammad stole from their religion, too, which involves the use of phallic symbols. But it would be fair to say that most people who look at the silver setting see the resemblance. Those pilgrims who are fortunate enough to get close to the black stone are expected to kiss it, because Muhammad kissed it.
Nice ritual. Nice symbols. What a nice religion! Who would expect that it would cause death, agony, and Hell for millions upon millions of the world's people?
For further information, an excellent article