Mecca is the holiest city in Islam and the spiritual centre of the world's 1.9 billion Muslims — the birthplace of the Prophet Muhammad (570 CE), the site of the Masjid al-Haram (the Grand Mosque, largest in the world), and the destination of the Hajj pilgrimage that every Muslim who is physically and financially able must complete once in their lifetime. Entry to Mecca is restricted to Muslims only; non-Muslims are prohibited by Saudi law. For Muslim visitors, the three days described here follow the Umrah (lesser pilgrimage) that can be performed year-round, distinct from the Hajj which requires specific dates in Dhul Hijjah. The Kaaba — the black cube at the centre of the Grand Mosque — is Islam's most sacred object; the act of Tawaf (circumambulation of the Kaaba) and Sa'i (walking between the hills of Safa and Marwa seven times) are the heart of both Umrah and Hajj. Modern Mecca has grown dramatically: the Abraj Al-Bait clock tower complex (the world's third-tallest building) looms over the mosque, and the city receives 15 million visitors annually.
Pilgrims enter the sacred state of Ihram (two white unstitched cloths for men; modest dress for women) at designated Miqat boundary points before entering Mecca — accompanied by the Talbiyah prayer.
The Kaaba — a cube structure draped in black Kiswah cloth embroidered with Quranic verses in gold — is circumambulated seven times counterclockwise. The Black Stone (Hajar al-Aswad) is touched or gestured to on each circuit.
After Tawaf, two units of prayer are performed near Maqam Ibrahim — the station of Ibrahim, where his footprints are preserved in the stone on which he stood to build the Kaaba, according to tradition.
Seven passages between the hills of Safa and Marwa (now enclosed within the mosque complex) commemorate Hajar's search for water for her son Ishmael — the act completed by drinking Zamzam water.
The 642 m mountain north of the Grand Mosque is where the first Quranic revelation was received by Muhammad in 610 CE — 1,600 steps to the narrow Cave of Hira, a major pilgrimage destination.
The granite hill on the plain of Arafat where Muhammad delivered his Farewell Sermon in 632 CE — standing here (Wuquf) on the 9th Dhul Hijjah is the central act of Hajj; Umrah pilgrims visit year-round.
The vast mosque at the edge of Arafat plain partly overlies the site where the Prophet prayed before his Farewell Sermon — one of the largest mosques in the world by capacity during Hajj.
The valley of Mina holds 100,000 permanent air-conditioned tents for Hajj pilgrims — the world's largest temporary city, uninhabited except during the five days of Hajj each year.
The three Jamarat pillars in Mina represent Satan and are pelted with pebbles during Hajj days — the ceremony commemorates Ibrahim's rejection of the devil's temptations. The bridge was rebuilt to modern safety standards after disasters.
The pre-dawn prayer in the Grand Mosque — when the Kaaba is illuminated and the courtyards are quietest — is considered the most spiritually powerful prayer time; the call to prayer echoes across all of Mecca simultaneously.
The Grand Mosque has been expanded 13 times; the current structure can accommodate 4 million worshippers simultaneously. The minarets (nine), the King Abdul Aziz Gate and the Zamzam well museum trace the mosque's 1,400-year evolution.
The former palace of King Abdul Aziz houses a museum of Meccan history — photographs of the pre-skyscraper city, Ottoman documents, early Quran manuscripts and artefacts from the pilgrimage routes.
The mountain where Muhammad sheltered for three nights during the Hijra migration to Medina (622 CE) — the cave is sacred to Sunni Muslims; a more challenging climb than Hira but historically significant.
The final act of Umrah and Hajj is a farewell Tawaf before leaving Mecca — seven circuits of the Kaaba at departure, traditionally performed while facing the Kaaba as long as possible when walking away.