Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Route 203 is a 5.5-mile state-numbered route in Boston, Massachusetts, United States, running from old U.S. Route 1 in Jamaica Plain east to Interstate 93/U.S. Route 1/Route 3 and Route 3A at Neponset. It runs along the Arborway, Morton Street and Gallivan Boulevard, all parkways formerly part of the Metropolitan District Commission system of parks and roads. Prior to the creation of the Massachusetts Department of Transportation in 2009, the route was owned and maintained by the Department of Conservation and Recreation.