Massachusetts Route 3A

Route 3A has two major posted segments, separated by a lengthy concurrency with Route 3 and US 3. Its southern portion parallels Route 3 from Cedarville in southern Plymouth to Neponset in the Dorchester area of Boston. Towns and cities that Route 3A traverse along its path include Plymouth, Kingston, Duxbury, Marshfield, Scituate, Cohasset, Hingham, Weymouth and Quincy.

North of Neponset, Route 3A runs, unsigned, concurrently with Route 3 and U.S. Route 3 to Burlington, before separating again (MassHighway counts the mileage along MA 3 between the two sections as part of MA 3A mileage).

The northern portion of which parallels U.S. Route 3 in northwestern Middlesex County. It stretches from Interstate 95 (Route 128) in Burlington to the New Hampshire state line, where it continues as Route 3A.

1 Route description
2 History
3 Junction list
4 References

Route description

Plymouth to Neponset

This segment parallels Route 3 from Cedarville in southern Plymouth to Neponset in the Dorchester area of Boston. Towns and cities that Route 3A traverse along its path include Plymouth, Kingston, Duxbury, Marshfield, Scituate, Cohasset, Hingham, Weymouth and Quincy.

Neponset to Burlington

This segment is concurrent with Route 3 (to Cambridge) and then U.S. Route 3 (from Cambridge to Burlington). As an 'A' route concurrent with its parents, this segment is not posted.

Burlington to Tyngsborough

This segment parallels US 3 from Interstate 95 (Route 128) in Burlington to the New Hampshire state line, where it continues as New Hampshire Route 3A. The part south of Route 113 in Tyngsborough is former US 3.

The section from Burlington to Billerica is currently being widened from 2 to 4 lanes.

History

From 1922 to 1926, Route 3A between Kingston and Quincy was New England Interstate Route 6A. In 1926, when New England Interstate Route 6 became Route 3, Route 6A became Route 3A.

In the 1930s Route 3A's route was shifted onto new alignments built to reduce traffic problems in several communities through which the highway traversed. This included a bypass of Hingham Square along Broad Cove Road and Otis Street along Hingham Harbor replacing the original route that took it down Lincoln Street to downtown Hingham then along North Street to Summer Street. Chief Justice Cushing Highway was built around the same time and Route 3A was put on this highway from south of the Hingham Harbor rotary through Cohasset to Scituate. This replaced a routing along long-existing roadways such as Country Way in Scituate, South and North Main Streets in Cohasset and East Street to Summer Street in Hingham. Along East Street from Hull Street to Summer, Route 3A shared the highway with Route 128 in the late 1920s and early 1930s.

In the 1950s and early 1960s Route 3A was extended to take over the original path of Route 3 south of Kingston to Plymouth and north of downtown Quincy to Neponset when Route 3 assumed its current freeway route. In between those locations, old Route 3 was designated Route 53. The section of old Route 3 from Cedarville south to the Sagamore Rotary near the Cape Cod Canal in Bourne is unnumbered.

Much of Route 3A is sometimes referred to as the "Cape Way" due to its history as the only major road to Cape Cod from Boston prior to the opening of Route 3. The "Cape Way" name is reflected in numerous business names along 3A's length.

The section of Route 3A south of the intersection with Route 113 in Tyngsborough (all but the northern few miles of the route) was formerly U.S. Route 3, prior to the construction of the Northwest Expressway, a freeway connection from I-95 in Burlington to the Everett Turnpike in Nashua, New Hampshire, which was given the U.S. Route 3 designation.

Junction list

County	Location	Mile	Roads intersected	Notes
Plymouth	Plymouth	0.0	Route 3	Southern terminus of southern portion of Route 3A at Route 3 Exit 2
		11.4	Plimoth Plantation Highway	Access to Route 3 Exit 4
		15.0	US 44	Access to Route 3 Exit 6
	Kingston	18.3	Route 3	Route 3 Exit 9
		18.7	Route 80	Eastern terminus of Route 80
		18.9	Route 106	Eastern terminus of Route 106; to Route 27 Signed access to Route 27/106 junction from Route 3A south is via Evergreen Street in Kingston Center
		20.3	Route 53	Southern terminus of Route 53
	Duxbury	20.6	Route 3	Route 3 Exit 10 Southbound ramps straddle Kingston line
		24.2	Route 14	Eastern terminus of Route 14
		25.0	Route 139
	Marshfield	27.7	Route 139	Southern end of concurrency with Route 139
	Marshfield	28.1	Route 139	Northern end of concurrency with Route 139
	Scituate	34.5	Route 123	Eastern terminus of Route 123
	Hingham	42.2	Route 228
Norfolk	Quincy	49.0	Route 53	Northern terminus of Route 53
Suffolk	Boston	53.6	I-93 / US 1 / Route 3	Beginning of unsigned concurrency with Route 3
Unsigned concurrency with Route 3 and US 3
Middlesex	Burlington	74.8	I-95 / US 3 / Route 128	Northern end of unsigned concurrency with US 3 I-95 Exit 33
		77.2	Route 62	Southern end of concurrency with Route 62
		77.8	Route 62	Northern end of concurrency with Route 62
	Billerica	82.4	Route 129	Southern end of concurrency with Route 129
	Billerica	83.6	Route 129	Northern end of concurrency with Route 129
	Lowell	87.3	Lowell Connector	Access to I-495 Exit 35 A-B-C
		87.7	Route 110	Southern end of concurrency with Route 110
		87.9	Route 110	Northern end of concurrency with Route 110
	Chelmsford	91.1	Route 4	Northern terminus of Route 4
	Chelmsford	91.8	Route 40	Eastern terminus of Route 40
	Tyngsborough	95.1	Route 113	Southern end of concurrency with Route 113 Tyngsborough Bridge crosses the Merrimack River
		95.3	Route 113	Northern end of concurrency with Route 113
		97.0	NH 3A	Northern terminus of Route 3A Continues as NH Route 3A into Hudson, New Hampshire
1.000 mi = 1.609 km; 1.000 km = 0.621 mi Concurrency terminus • Closed/Former • Incomplete access • Unopened

References

^ ^a ^b ^c Executive Office of Transportation, Office of Transportation Planning - 2005 Road Inventory

Road transportation infrastructure of Cape Cod

U.S. Routes	US 6

State Routes	Route 3 Route 3A Route 6A Route 25 Route 28 Route 28A Route 39 Route 124 Route 130 Route 132 Route 134 Route 137 Route 149 Route 151

State Roads	Sandwich Road

Bridges	Bourne Bridge Sagamore Bridge

See also:	Cape Cod Canal Tunnel Southside Connector