Mecca is the capital of Mecca Province in the Hejaz region of western Saudi Arabia and the holiest city in Islam. It is 70 km (43 mi) inland from Jeddah on the Red Sea, in a narrow valley 277 m (909 ft) above sea level. Its last recorded population was 2,385,509 in 2022. Its metropolitan population in 2022 is 2.4 million, making it the third-most populated city in Saudi Arabia after Riyadh and Jeddah. Around 44.5% of the population are Saudi citizens and around 55.5% are foreigners from other Muslim countries. Pilgrims more than triple the population number every year during the Ḥajj pilgrimage, observed in the twelfth Hijri month of Dhūl-Ḥijjah. With over 10.8 million international visitors in 2023, Mecca was one of the 10 most visited cities in the world.

The Hejaz is a region that includes the majority of the west coast of Saudi Arabia, covering the cities of Mecca, Medina, Jeddah, Tabuk, Yanbu, Taif and Baljurashi. It is thus known as the "Western Province", and it is bordered in the west by the Red Sea, in the north by Jordan, in the east by the Najd, and in the south by the Region of 'Asir. Its largest city is Jeddah, which is the second-largest city in Saudi Arabia, with Mecca and Medina, respectively, being the fourth- and fifth-largest cities in the country.