Medina is Islam's second holiest city, home to the Prophet's Mosque (Masjid an-Nabawi) where Prophet Muhammad is buried alongside the first two Caliphs. The city served as the first Islamic state's capital and witnessed the establishment of the Muslim community (Ummah) after the Hijra in 622 CE. Today, millions of pilgrims visit annually to pay respects at the Prophet's tomb, making it a central destination for Islamic spiritual journey and heritage.