Boston Common, located near the Financial District and Beacon Hill, is the oldest public park in the United States. Along with the adjacent Boston Public Garden, it is part of the Emerald Necklace, a string of parks designed by Frederick Law Olmsted to encircle the city. The Emerald Necklace includes Jamaica Pond, Boston's largest body of freshwater, and Franklin Park, the city's largest park and home of the Franklin Park Zoo. Another major park is the Esplanade, located along the banks of the Charles River. The Hatch Shell, an outdoor concert venue, is located adjacent to the Charles River Esplanade. Other parks are scattered throughout the city, with the major parks and beaches located near Castle Island; in Charlestown; and along the Dorchester, South Boston, and East Boston shorelines.
The Emerald necklace is a string of what?
parks