also provide service and connect with other railroads. Massachusetts has a total of of freight trackage in operation. Air service Boston Logan International Airport served 33.5million passengers in 2015 (up from 31.6million in 2014) through 103 gates. Logan, Hanscom Field in Bedford, and Worcester Regional Airport are operated by Massport, an independent state transportation agency. Massachusetts has 39 public-use airfields and more than 200 private landing spots. Some airports receive funding from the Aeronautics Division of the Massachusetts Department of Transportation and the Federal Aviation Administration; the FAA is also the primary regulator of Massachusetts air travel. Roads There are a total of of interstates and other highways in Massachusetts. Interstate90 (I-90, also known as the Massachusetts Turnpike), is the longest interstate in Massachusetts. The route travels generally west to east, entering Massachusetts at the New York state line in the town of West Stockbridge, and passes just north of Springfield, just south of Worcester and through Framingham before terminating near Logan International Airport in Boston. Other major interstates include I-91, which travels generally north and south along the Connecticut River; I-93, which travels north and south through central Boston, then passes through Methuen before entering New Hampshire; and I-95, which connects Providence, Rhode Island with Greater Boston, forming a partial loop concurrent with Route128 around the more urbanized areas before continuing north along the coast into New Hampshire. I-495 forms a wide loop around the outer edge of Greater Boston. Other major interstates in Massachusetts include I-291, I-391, I-84, I-195, I-395, I-290, and I-190. Major non-interstate highways in Massachusetts include U.S. Routes 1, 3, 6, and 20, and state routes 2, 3, 9, 24, and 128. A great majority of interstates in Massachusetts were constructed during the mid-20th century, and at times were controversial, particularly the intent to route I-95 northeastwards from Providence, Rhode Island, directly through central Boston, first proposed in 1948. Opposition to continued construction grew, and in 1970 Governor Francis W. Sargent issued a general prohibition on most further freeway construction within the I-95/Route 128 loop in the Boston area. A massive undertaking to bring I-93 underground in downtown Boston, called the Big Dig, brought the city's highway system under public scrutiny for its high cost and construction quality. Government and politics Massachusetts has a long political history; earlier political structures included the Mayflower Compact of 1620, the separate Massachusetts Bay and Plymouth colonies, and the