Connecticut Route 80
|Maintained by ConnDOT|
|Length:||25.91 mi (41.70 km)|
|Existed:||1932 – present|
|West end:||Route 17 in New Haven|
| I‑91 in New Haven
Route 9 in Deep River
|East end:||Route 154 in Deep River|
Route 80 is a 25.91-mile-long (41.70 km) secondary east–west state route in Connecticut from New Haven to Deep River. It serves as a more inland alternate route to US 1 in eastern New Haven County and Middlesex County.
Route 80 begins at the junction of I-91 and Route 17 in New Haven (at Exit 8). Route 17 splits off and heads northward right after the exit. Route 80 begins as a 4-lane principal arterial road in New Haven, East Haven and North Branford, where it overlaps Route 22 for 1.50 miles (2.41 km). It becomes 2 lanes from North Branford to Madison. From Killingworth to its terminus in Deep River, it becomes a rural minor arterial road. In Deep River, Route 80 briefly overlaps Route 145, then has an interchange with Route 9 about 0.6 miles (0.97 km) before its terminus at Route 154.
In 1818, a toll road was chartered running from the Boston Post Road at the Guilford-Madison town line northeast through Killingworth center, then east to Deep River, ending at the Middlesex Turnpike. The turnpike, known as the Pettipauge and Guilford Turnpike, used Green Hill Road in Madison then modern Route 80 to Deep River. In 1824, another turnpike was built, beginning in the Fair Haven section of New Haven, heading eastward along modern Route 80, and ending at the Pettipauge and Guilford Turnpike in Killingworth center. This was known as the Fairhaven Turnpike.
In 1922, when Connecticut first publicly signed its state highways with route numbers, several new numbered routes where created from these two turnpikes. From Fair Haven to North Branford center, State Highway 135 was created. Old Highway 135 continued south from North Branford center along modern Route 139 to the Boston Post Road. The eastward continuation of the old Fairhaven Turnpike between North Branford center and the village of North Guilford was designated as State Highway 140. The portion of the old Pettipaue and Guilford Turnpike between Killingworth center and Deep River center became State Highway 175.
Modern Route 80 was established as part of the 1932 state highway renumbering from old highways 175, 140, and the east–west portion of 135. In 1940, its east end was relocated to US 1 in Old Saybrook along Warsaw Street, Main Street, Middlesex Turnpike, and Essex Road. In the 1950s, it was extended west to Route 10 in New Haven along Middletown Avenue, State Street, Edwards Street, Munson Street, and Henry Street to Route 10 (Sherman Avenue). In 1962, the western end was truncated to its current location at Route 17. In 1966, with the opening of Route 9, the eastern end of Route 80 was truncated and rerouted to its current location.
|New Haven||New Haven||0.00||0.00||Route 17 north – North Haven|
|0.04||0.06||I‑91 – Meriden||Access from I-91 only; to access I-91 from Route 80 follow Route 17|
|0.44||0.71||Route 103 north – North Haven|
|East Haven||2.37||3.81||Route 100 south – East Haven|
|North Branford||4.80||7.72||Route 22 north – Northford||Begin Multiplex with CT 22|
|6.11||9.83||Route 139 south – Branford|
|6.30||10.14||Route 22 south – Guilford||End Multiplex with CT 22|
|Guilford||9.48||15.26||Route 77 – North Guilford, Guilford|
|Madison||14.08||22.66||Route 79 – Durham, Madison|
|Middlesex||Killingworth||18.19||29.27||Route 81 – Clinton, Higganum|
|Deep River||21.60||34.76||Route 145 south – Clinton||Begin Multiplex with CT 145|
|21.95||35.33||Route 145 north – Chester||End Multiplex with CT 145|
|25.36||40.81||Route 9 – Essex, Haddam||CT 9 Exit 5|
|25.91||41.70||Route 154 – Haddam, Centerbrook|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi