Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Back Bay Fens, most commonly called simply The Fens, is a parkland and urban wild in Boston, Massachusetts, in the United States. Designed by Frederick Law Olmsted to serve as a link in the Emerald Necklace park system, the Fens gives its name to the Fenway-Kenmore neighborhood, and thereby to Fenway Park, home of the Boston Red Sox. The Back Bay Fens is a large picturesque park that forms part of Boston's Emerald Necklace. It is essentially an ancient spot of saltwater marshland that has been surrounded by dry land, disconnected from the tides of the Atlantic Ocean, and landscaped into a park with fresh water within. The park is also known as the Fens or the Fenway. The latter term can also refer to the surrounding neighborhood.