Key West is an island and city in the Straits of Florida, USA. It is the southernmost city in the contiguous United States and the westernmost island connected by highway in the Florida Keys. The island, which is about 4 miles (6.4 km) long and 1 mile (1.6 km) wide, has a population of approximately 25,000 and was visited by 2.25 million tourists in 2016.