Baltimore is the largest independent city in the United States and the largest city and cultural center of the U.S. state of Maryland. The city is located in central Maryland along the tidal portion of the Patapsco River, an arm of the Chesapeake Bay. Baltimore is sometimes referred to as Baltimore City in order to distinguish it from surrounding Baltimore County. Founded in 1729, Baltimore is the largest U.S. seaport in the mid-atlantic and is situated closer to major Midwestern markets than any other major seaport on the East Coast. Baltimore's Inner Harbor was once the second leading port of entry for immigrants to the United States and a major manufacturing center. The harbor is now home to Harborplace, a shopping, entertainment, and tourist center, and the National Aquarium in Baltimore. According to Forbes, the city of Baltimore was rated 3rd best place to shop in 2010. After a decline in manufacturing, Baltimore shifted to a service-oriented economy. Johns Hopkins University and Johns Hopkins Hospital are now the city's largest employers.