A tolled highway connecting the major cities of New York was first proposed as early as the 1940s. The first section of the Thruway, between Utica and Rochester, opened on June 24, 1954. The remainder of the mainline and many of its spurs connecting to highways in other states and provinces were built in the 1950s. When the Interstate Highway System was created in 1957, much of the Thruway system was included as portions of Interstate 87 (I-87), I-90, and I-95. Other segments became part of I-190 and I-287 shortly afterward. Today, the system comprises six highways: the New York – Ripley mainline, the Berkshire Connector, the Garden State Parkway Connector, the New England Thruway (I-95), the Niagara Thruway (I-190), and the Cross Westchester Expressway (I-287). The portion of I-84 in New York was part of the Thruway system from 1991 to 2010.