Route 64 is part of the old US 6A, and was designated in 1967.

In the 1920s, this road was part of New England Interstate Route NE-3, a road leading from New York State to Cape Cod. Most of this road became part of US 6 in 1927. In 1929 US 6 was already located to the north, via Thomaston; it may have gone through Middlebury for a year or two.

On Jan. 1, 1932, during the Great Renumbering, today's Route 64 became part of the original Route 14, which extended nearly 90 miles inside the state, from Woodbury to Sterling. On Jan. 1, 1941, most of Route 14 was designated US 6A, to provide an alternate to US 6.

In the mid-1960s, as Interstate 84 was being constructed through Waterbury, the state Highway Department proposed another route number change, to better reflect the evolving highway system. US 6A east of I-84, from Southington to Willimantic, would become the new Route 66. US 6A through Waterbury, a route duplicated by the new I-84, would no longer be signed. The section to the west, leading to Woodbury, would be given another available route number: 64. The proposed changes were announced in late 1965, and took place in 1967.

Old Sherman Hill Road

In Woodbury, Route 64 is Sherman Hill Road. A parallel route, Old Sherman Hill Road, is evidently an older, more serpentine alignment. I'm guessing the newer Sherman Hill Road was built around 1930. A two-lane bridge of new (and Route 64) over old was built in 1931.

Route 64 freeway (ok, a bypass); still would have been cool

Between the vicinity of Route 63 and I-84 in Middlebury, Route 64 serves heavy traffic. The incomplete interchange at I-84 and Route 63, with access to and from the west only, contributes to this: traffic to and from Waterbury uses Route 64 to access I-84.

In 1973, proposals from the town of Middlebury and the Central Naugatuck Council of Governments included a bypass for Route 64, running south of the current alignment, between Rose Court and Woodside Avenue. The bypass would include an interchange at Route 63. This was never implemented, but the town's 2001 development plan draft still includes the bypass as a regional priority. Completing the Route 63/I-84 interchange is also proposed as a way to relieve Route 64 traffic.

• "To renumber Connecticut Road." New York Times, Nov. 15, 1940.
• "Highway Dept. Explains Route Number Changes." Hartford Courant, Nov. 30, 1965.
• Draft Plan of Development, Town of Middlebury (Conn.), March 2001.
• Nationalbridges.com National Bridge Inventory - 09 - Connecticut Bridge query results - route 64, Accessed 29 August 2009.