Cyrene, also sometimes anglicized as Kyrene, was an ancient Greek colony and Roman city near present-day Shahhat in northeastern Libya in North Africa. It was part of the Pentapolis, an important group of five cities in the region, and gave the area its classical and early modern name Cyrenaica.

Cyrene lies on a ridge of the Jebel Akhdar uplands. The archaeological remains cover several hectares and include several monumental temples, stoas, theatres, bathhouses, churches, and palatial residences. The city is surrounded by the Necropolis of Cyrene. Since 1982, it has been a UNESCO World Heritage Site. The city's port was Apollonia (Marsa Sousa), located about 16 kilometres (10 mi) to the north.

The city was attributed to Apollo and the legendary etymon Cyrene by the Greeks themselves but it was probably actually colonized by settlers from Thera (modern Santorini) in the late seventh century BC. It was initially ruled by a dynasty of monarchs called the Battiads, who grew rich and powerful as a result of successive waves of immigration and the export of horses and silphium, a medicinal plant. By the fifth century BC, they had expanded their control over the other cities of Cyrenaica. It became the seat of the Cyrenaics, a school of philosophy in the fourth century BC, founded by Aristippus, a disciple of Socrates. In the Hellenistic Age, the city alternated between being part of Ptolemaic Egypt and the capital of an independent kingdom. It was also an important Jewish hub. In 96 BC, it passed to the Roman Republic and became part of the province of Crete and Cyrenaica. The city was destroyed by Jewish fighters in AD 115 during the Diaspora revolt, and slowly rebuilt over the following century. Earthquakes in 262 and 365 devastated the city, but some habitation continued through the early Byzantine period and the Muslim conquest of the Maghreb in 642, after which the site was abandoned until the establishment of an Italian military base on the site in 1913. Excavations have been ongoing since that time.