Medina, officially Al Madinah Al Munawwarah (Arabic: المدينة المنورة, romanized: al-Madīnah al-Munawwarah, lit. 'The Enlightened City', Hejazi pronunciation: [almadiːna almʊnawːara], and also commonly simplified as Madīnah or Madinah (المدينة, al-Madina, Hejazi pronunciation: [almadiːna]), is the second-holiest city in Islam and the capital of Medina Province in the Hejaz region of western Saudi Arabia. As of 2020, the estimated population of the city is 1,488,782, making it the fourth-most populous city in the country. Located at the core of the Medina Province in the western reaches of the country, the city is distributed over 589 km² (227 sq mi), of which 293 km² (113 sq mi) constitutes the city's urban area, while the rest is occupied by the Hejaz Mountains, empty valleys, agricultural spaces and older dormant volcanoes.

Medina is generally considered to be the "cradle of Islamic culture and civilization". The city is considered to be the second-holiest of three key cities in Islamic tradition, with Mecca and Jerusalem serving as the holiest and third-holiest cities respectively. Al-Masjid al-Nabawi (lit. 'The Prophet's Mosque') is of exceptional importance in Islam and serves as burial site of the last Islamic prophet, Muhammad, by whom the mosque was built in 622 CE. Observant Muslims usually visit his tomb, or rawdhah, at least once in their lifetime during a pilgrimage known as Ziyarat, although this is not obligatory. The original name of the city before the advent of Islam was Yathrib (Arabic: يَثْرِب), and it is referred to by this name in Chapter 33 (Al-Aḥzāb, lit. 'The Confederates') of the Quran. It was renamed to Madīnat an-Nabī (lit. 'City of the Prophet' or 'The Prophet's City') after Muhammad's death and later to al-Madinah al-Munawwarah (lit. 'The Enlightened City') before being simplified and shortened to its modern name, Madinah (lit. 'The City'), from which the English-language spelling of "Medina" is derived. Saudi road signage uses Madinah and al-Madinah al-Munawwarah interchangeably.

The city existed for over 1,500 years before Muhammad's migration from Mecca, known as the Hijrah. Medina was the capital of a rapidly-increasing Muslim caliphate under Muhammad's leadership, serving as its base of operations and as the cradle of Islam, where Muhammad's umma (lit. 'nation')—composed of Medinan citizens (Ansar) as well as those who immigrated with Muhammad (Muhajirun), who were collectively known as the Sahabah—gained huge influence. Medina is home to three prominent mosques, namely al-Masjid an-Nabawi, Quba Mosque, and Masjid al-Qiblatayn, with the Quba Mosque being the oldest in Islam. A larger portion of the Qur'an was revealed in Medina in contrast to the earlier Meccan surahs.

Much like most of the Hejaz, Medina has seen numerous exchanges of power within its comparatively short existence. The region has been controlled by Jewish-Arabian tribes (up until the fifth century CE), the ʽAws and Khazraj (up until Muhammad's arrival), Muhammad and the Rashidun (622–660), the Umayyads (660–749), the Abbasids (749–1254), the Mamluks of Egypt (1254–1517), the Ottomans (1517–1805), the First Saudi State (1805–1811), Muhammad Ali Pasha (1811–1840), the Ottomans for a second time (1840–1918), the Sharifate of Mecca under the Hashemites (1918–1925) and finally is in the hands of the present-day Kingdom of Saudi Arabia (1925–present).

In addition to visiting for Ziyarah, tourists come to visit the other prominent mosques and landmarks in the city that hold religious significance such as Mount Uhud, Al-Baqi' cemetery and the Seven Mosques among others. Recently, after the Saudi conquest of Hejaz.