3.08 miles; a four-lane expressway from I-91 in North Haven to Route 10 in Hamden. Its one numbered exit is exit 1. There's a nice sweeping interchange at I-91, including a connection to Bailey Road, and a partial interchange at Route 10, allowing direct access from Route 10 southbound.

Route 40 crosses over the Wilbur Cross Parkway (Route 15) with no interchange at all; this is the only place two freeways do this in Connecticut.

Route 40 is the remaining vestige of various plans for a New Haven bypass, dating to the early 1940s. The bypass would have connected a proposed Route 10 freeway in Hamden to Interstate 95 in Branford.

The first bypass: Route 22

When the Wilbur Cross Parkway (Route 15) was fully open in 1949, there was still no easy way around New Haven to shore points east. Early plans for the area expressway network showed a proposed eastward spur from Route 15 to East Haven; however, that was never built.

To help guide traffic around northern outskirts of New Haven, a new numbered route was created incorporating old routes 168 and 141, as well as most of Route 139. This new route -- Route 22 -- was created in 1951, and today zigzags along the modern Route 40 corridor.

Plans for an expressway bypass

Statewide expressway plans in the 1960s included a new highway around New Haven, connecting Route 10 in Hamden to I-95 in Branford. The Tri-State Transportation Council plans called this the Route 22 Expressway. In 1968, when the federal government asked states to nominate additions to the interstate highway system, Connecticut's position was that the the system should not be expanded; however, if it was, the state would nominate a twelve-mile loop around New Haven. This was not granted.

The Mount Carmel Connector

In the early 1960s, the state planned three New Haven-area connectors from I-91 to US 5 and Route 10. One of these was the Mount Carmel Connector, running north and west from Interstate 91 at Bailey Street in North Haven to Route 10 near Ives Street in Hamden.

By 1964, planners had arrived at a location and treatment for the Connector close to what was eventually built. A semi-directional three-level "T" interchange would be built at I-91, with ramps from the Connector to Bailey Street; this was built as planned. A nonstandard interchange involving a divided Dixwell Avenue at State Street was not built as planned; instead, a more conventional set of hook ramps were built at Dixwell Avenue and Devine Street.

A partial interchange was planned at the Wilbur Cross Parkway. There is no interchange at all today: the only place in Connecticut where two expressways cross with no access between them. The original plan would have provided three ramps:

• 40 NB to 15 NB
• 40 NB to 15 SB
• 15 SB to 40 NB

A full trumpet interchange was planned at the Connector's terminus at Route 10. The inner loop ramp to Route 10 southbound was omitted, and traffic instead makes a left turn at a traffic signal.

Route 40 opens in sections

The first part of the Connector, from I-91 to Dixwell Avenue, opened in 1972. The state's numbering, SR 724, was not signposted. The remaining 1.8-mile section to existing Route 10, in the design stages, was referred to as the Relocation of Route 10.

In 1976, the remainder opened, extending SR 724 to Route 10. The state had been referring to the new freeway as the Route 10 connector up until the time it opened. Signs for Exit 10 on I-91 once labeled the highway as "To [10]".

Renumber as Interstate 991. This would be (temporarily) the highest-numbered interstate in the world. This idea is original, though you'll see it in other places.

• "Survey Plots Expressway Plans." Hartford Times, Jan. 1, 1963.
• "Tentative Path of Mount Carmel Connector: Early Start is Sought." New Haven Register, May 24, 1964.
• Tri-State Transportation 1985; an interim plan. Tri-State Transportation Commission, 1966.
• "The Relocation of Route 10 in New Haven Coounty, from Whitney Avenue (Route 10) in Hamden, on the West to the Vicinity of State Street (Route US 5), and Dixwell Avenue (Route 717) in North Haven on the East." Federal Highway Administration, Hartford, Conn. Connecticut Div., Sept. 18, 1973.
• "1975 Master Transportation Plan." Connecticut Department of Transportation.

• Route 10
• Route 22, a smaller, older bypass route
• CT 40 expressway (Steve Anderson)
• Route 40 exit list (Tripod) (Neil Kelly)
• Aerial photos (Greg Amy; western end at Route 10)
• Route 40 Ends (Photos; Doug Kerr at state-ends.com)

About 50 miles; from New York state line to US 20 in Pittsfield, Mass. (It crosses through Connecticut in Sharon and Salisbury.) It appears not to be numbered in New York at this time. 17.86 miles in Connecticut.

Route 41 is one of the most scenic routes in the state. The Danbury News-Times wrote:

"This 4-mile country road tucked away in the hills of northeastern Connecticut's Litchfield County is a treasure waiting to be discovered. Like something out of a Norman Rockwell painting, perfectly restored colonial homes, churches and shops dot the streets of downtown Sharon...In the fall, the front comes early to this region, and with it comes some of the most brilliant foliage you'll ever see."

Commissioned in 1932. Before that, it was part of New England route NE-4, the precursor to US 7; and part of US 7 as well, which used to leave Connecticut and follow NY 22 to New York City.

Route 41 is the only state highway in Connecticut to touch two state borders.

Route 41 Ends (Photos; Doug Kerr at state-ends.com)

13.58 miles; from Route 67 in Oxford to Route 10 in Cheshire. Passes by towering Mount Sanford (880 feet). It's a four-lane divided highway for a stretch in Beacon Falls (an inherited portion of former Route 8).

Route 42 was commissioned in 1963, between Routes 10 and 63 only, and extended westward in 1967 or 1968. The Pines Bridge Road section east of Route 8 in Beacon Falls was formerly SR 503. The Cheshire portion was added on Aug. 1, 1962 as unsigned SR 738; the later addition of a Bethany section probably prompted the redesignation to a signed route.

Route 42 expressway

In the 1960s, the South Central Connecticut Planning Region proposed a freeway in the Route 42 corridor, from Route 8 in Beacon Falls to the Wharton Brook Connector (SR 702) at I-91 exit 13, and beyond to a proposed Route 17 freeway. This seemed to fall squarely under "future needs" and apparently was not pursued with great vigor.

In January 1999, a bill was introduced in the General Assembly to prohibit trucks on Route 42 between Cheshire and Bethany (presumably routes 10 and 69). The road is quite narrow and sinuous through the region.

In 1999, a 90-degree curve at Back Rimmon Road in Beacon Falls (west of Route 8) was eliminated as Route 42 was realigned in the area: it now goes straight past the T-intersection and gradually curves to the north. A hump in Route 42 was also flattened to make the road safer.

"If someone wishes to travel faster than me and I am travelling on Connecticut Route 42 between Cheshire and Prospect then they can bloody well take it out in wishing... If they want to pass me on the left, then that is their privilege to do so, but they stand a good chance of getting killed in the process. Visibility is usually no more than 100 feet."

• "Highway Unit Cancels '10A' Designation.' New Haven Register, Aug. 1, 1962.
• "Work to make Route 42 safer." The Republican-American [Waterbury, Conn.], April 16, 1999.

Route 42 Ends (Photos; Doug Kerr at state-ends.com)

5.06 miles; from Route 4 to Route 63, entirely in Cornwall.

Commissioned in 1932, from the old Route 132; this route, from Cornwall to Canaan, also included the top 4.95 miles of what is now Route 63 to US 7.

In 1952, Route 63 was extended to Canaan at Route 43's expense.

See the US 44 page.