Miami, officially the City of Miami, is the cultural, economic and financial center of South Florida and the seat of Miami-Dade County, the most populous county in Florida. The city covers an area of about 56 square miles (150 km2) between the Everglades to the west and Biscayne Bay to the east. Miami is the sixth most densely populated major city in the United States with an estimated 2018 population of 470,914. The Miami metropolitan area is home to 6.1 million people, the second-most populous in the southeastern United States and the seventh-largest in the nation. The city has the third tallest skyline in the U.S. with over 300 high-rises, 55 of which exceed 490 ft (149 m).Miami is a major center and leader in finance, commerce, culture, media, entertainment, the arts, and international trade. The metro area is by far the largest urban economy in Florida and the 12th largest in the United States, with a GDP of $344.9 billion as of 2017. In 2018, Miami was classified as an Alpha level global city by the GaWC. In 2019, Miami ranked seventh in the United States and 31st among global cities in terms of business activity, human capital, information exchange, cultural experience, and political engagement. According to a 2018 UBS study of 77 world cities, the city was ranked as the third-richest in the United States and the eighth-richest in the world in terms of purchasing power. Miami is nicknamed the "Capital of Latin America" and is the largest city with a Cuban-American plurality.Greater Downtown Miami has one of the largest concentrations of international banks in the United States, and is home to many large national and international companies. The Health District is a major center for hospitals, clinics, and the biotechnology and medical research industries. PortMiami is the busiest cruise port in the world in both passenger traffic and cruise lines, and refers to itself as the "Cruise Capital of the World". Miami is also a major tourism hub for international visitors, ranking second in the country after New York City.