Faro (/ˈfɑːroʊ/ FAR-oh, Portuguese: [ˈfaɾu] ^ⓘ), officially the City of Faro (Portuguese: Cidade de Faro), is a city and a municipality in southern Portugal. It is the capital of both the Algarve region and the Faro District, as well as the southernmost city on the Portuguese mainland. Faro municipality covers an area of 202.57 km² (78.21 sq mi) and, as of 2024, had 70,347 inhabitants, making it the second most populous municipality in the Algarve after Loulé. The city proper had 46,299 inhabitants in 2021, the largest urban population in the region. Faro lies on the shore of the Ria Formosa lagoon, a protected nature reserve and hosts the region’s international airport and university.

Founded as Ossonoba in antiquity, Faro was a settlement during the Phoenician and Roman periods and later served as a Moorish port known as Santa Maria Ibn Harun. It became part of the Kingdom of Portugal in 1249 and was elevated to city status in 1540. Since 1756, following the devastation of the Lisbon earthquake, Faro has been the administrative capital of the Algarve.

The municipalities of Faro, Olhão and Loulé, due to their proximity, shared infrastructure and commuter links can be considered^{[by whom?]} an intermunicipal community^{[citation needed]} with a population of 191,563 inhabitants as of 2024. A bus rapid transit system connecting this community is under development to connect these municipalities.

Roman Empire 206 a.C.–411
Alans 411–560
Byzantine Empire 560–624
Visigothic Kingdom 624-711
Umayyad Caliphate 711-756
Emirate of Córdoba 756-929
Caliphate of Córdoba 929-1018
Taifa of Santa Maria do Algarve 1018-1051
Taifa of Seville 1051-1091
Almoravid dynasty 1091-1145
Taifa of Badajoz 1145-1155
Almohad Caliphate 1155-1249
Kingdom of Portugal 1249-1580
Iberian Union 1580-1640
Kingdom of Portugal 1640-1910
Portugal 1910-present

The Ria Formosa lagoon attracted humans from the Palaeolithic age until the end of prehistory. The first settlements date from the fourth century BC, during the period of Phoenician colonization of the western Mediterranean. At the time, the area was known as Ossonoba, and was the most important urban centre of southern Portugal and commercial port for agricultural products, fish, and minerals.

Between the second and eighth centuries, the city was under the domain of the Romans, then the Byzantines, and later Visigoths, before being conquered by the Arabic-speaking Muslims known as Moors in 713. From the third century onwards and during the Visigothic period, it was the site of an Episcopal see, the Ancient Diocese of Ossonoba (306-688). The Byzantine presence has endured in the towers of the city walls that were built during the Byzantine period.

With the advent of Moorish rule in the eighth century, Ossonoba retained its status as the most important town in the southwest corner of the Iberian Peninsula. In the 9th century, after a revolt led by Yahia Ben Bakr who was succeeded in office by his son, Bakr Ben Yahia, it became the capital of a short-lived princedom and was fortified with a ring of defensive walls. At this time, in the 10th century, the name Santa Maria began to be used instead of Ossonoba. By the 11th century, the town was known as Santa Maria Ibn Harun.

During the Second Crusade soon after the Anglo-Norman forces took Lisbon in 1147 a detachment of this group sacked Faro, which was still by then under Muslim rule, on their way to the Holy Land. Again in 1217, during the Fifth Crusade, a Frisian fleet of crusaders on their way to Acre, sacked and burned the city.