The jewel in the Temple Mount crown is the gold-plated Dome of the Rock, the enduring symbol of the city and undoubtedly one of the most photographed buildings on earth. As its name suggests, the dome covers a slab of stone sacred to both the Muslim and Jewish faiths. According to Jewish tradition, it was here that Abraham prepared to sacrifice his son. Islamic tradition has the Prophet Mohammed ascending to heaven from this spot.
The building was constructed between 688 and 691 CE under the patronage of the Umayyad caliph Abd al-Malik. His motives were shrewd as well as pious – the caliph wanted to instil a sense of pride into the local Muslim population and keep them loyal to Islam. He also wanted to make a statement to Jews and Christians: Islam was both righteous and all-powerful, so it could build a structure more splendid than any Christian church on a location that was the location of the Jewish Holy of Holies, thus superceding both religions.
Abd al-Malik had his Byzantine architects take as their model the rotunda of the Holy Sepulchre. But not for the Muslims the dark, gloomy interiors or austere stone facades of the Christian structures; instead, their mosque was covered inside and out with a bright confection of mosaics and scrolled verses from the Quran, while the crowning dome was covered in solid gold that shone as a beacon for Islam.
A plaque was laid inside honouring Abd al-Malik and giving the date of construction. Two hundred years later the Abbasid caliph Al-Mamun altered it to claim credit for himself, neglecting to amend the original date. In 1545, Süleyman the Magnificent ordered that the much-weathered exterior mosaics be removed and replaced with tiles. These were again replaced during a major restoration in the 20th century. The original gold dome also disappeared long ago, melted down to pay off some caliph’s debts, and is now covered with 1.3mm of gold donated by the late King Hussein of Jordan. The 80kg of gold cost the king US$8.2 million – he sold one of his homes in London to pay for it.
Essentially, however, what you see today is the building as conceived by Abd al-Malik. Inside, lying centrally under the 20m-high dome and ringed by a wooden fence, is the rock from which it is said Mohammed began his miraj (ascension to heaven). According to the Quran, the stone also wanted to join him in heaven and began to rise from the earth; Mohammed pushed the stone down with his foot, leaving a footprint on the rock (supposedly still visible in one corner). Jewish tradition also has it that this marks the centre of the world. Steps below the rock lead to a cave known as the Well of Souls, where the voices of the dead are said to be heard falling into the river of paradise and on to eternity. The mihrab in the sanctuary is said to be the the oldest in the Islamic world.
There are nine gates connecting Temple Mount to the surrounding narrow streets, but non-Muslims are allowed to enter only at the Bab al-Maghariba/Sha’ar HaMugrabim (Gate of the Moors), reached via an ugly wooden walkway on the southern side of the Western Wall plaza. Line up early (if you don't, you're unlikely to get inside), and bear in mind that the site closes on Muslim holidays and is only open in the morning during Ramadan. You'll need to have your passport to make it through the security check. Note that it's possible to exit the enclosure by all open gates, not just Bab al-Maghariba.
Be aware that caretakers at the enclosure run a scam whereby they force any visitors deemed to be insufficiently clothed to purchase a shawl and wear it sarong-style. Needless to say, the sarongs are overpriced and receipts are unavailable. To avoid being subjected to this, both men and women should wear long pants or skirts (definitely no shorts) and have their shoulders, backs and decolletages covered.
It is not possible for non-Muslims to enter the Al-Aqsa Mosque or the Dome of the Rock; trying to do so is both disrespectful and unwise.
Note that the enclosure is often closed to visitors during times of political unrest.