Puerto Williams is a city, port, and naval base located on Navarino Island in Chile. It faces the Beagle Channel and serves as the capital of the Chilean Antarctic Province within the Magellan and Chilean Antarctica Region. The settlement claims the title of the world's southernmost city and functions as the main city inside the Cape Horn Biosphere Reserve. It also administers the communes of Cabo de Hornos and the Chilean Antarctic Territory.
Founded in 1953 as Puerto Luisa, the town was later renamed in honor of John Williams Wilson, who established Fuerte Bulnes in the Strait of Magellan. While it has historically served primarily as a naval base—with the Chilean Navy operating the Guardiamarina Zañartu Airport, a hospital, and nearby meteorological stations—the demographic makeup has shifted since the late 20th century. During this period, the civilian population increased while the number of navy personnel decreased, with economic activity growing through tourism and support for scientific research.