The Origin Tremont gets it's name from the Original 3 hills of Boston. Originally, a thin bridge of land at its south end connected Boston to the mainland. The Charles River divided the peninsula from the mainland on the west and to the north. Along the riverbank stretched the Back Bay, a series of mud flats and salt marshes covered by water at high tide. On the east, an extension of the harbor known as Town Cove divided Boston into the North End and the South End. Through the center of the peninsula rose the Trimountain, three hills known as Mount Vernon, Beacon Hill, and Pemberton Hill.
		Boston's Growth By 1867 Boston had expanded from the original settlement of 786 acres to more than 4,000 acres as a result of numerous landfill projects beginning as early as 1803. Mount Vernon and Pemberton Hill were leveled, as was much of Beacon Hill, which is now only a fraction of its former height. Much of the earth removed from those sites went into filling the coves along Boston’s coast. By the mid-1800s, most of the coves had disappeared. Fill on both sides of the narrow neck that connected the peninsula and the mainland created a new South End, and two new neighborhoods—the Back Bay and South Boston—emerged on land reclaimed from the Charles River and Boston Harbor. As a result, central Boston was no longer a peninsula, but was joined by land to the communities on its south and west.