Medina lies 2,050 feet (625 metres) above sea level on a fertile oasis. It is bounded on the east by an extensive lava field, part of which dates from a volcanic eruption in 1207 CE. On the other three sides, the city is enclosed by arid hills belonging to the Hejaz mountain range. The highest of these hills is Mount Uḥud, which rises to more than 2,000 feet above the oasis.
Al-Masjid an-Nabawi is the second mosque built in the history of Islam and is now one of the largest mosques in the world. It is the second-holiest site in Islam, after al-Masjid al-Haram in Makkah.