Thanks to the Lowell National Historical Park’s Facebook post for reminding us a bit about the history of the Lowell Connector. This citation comes from bostonroads.com:
The Lowell Connector was opened officially on October 24, 1962. However, the ramps to I-495 did not open until one year later, when the Outer Circumferential Highway was completed through the area…
EXPRESSWAY SERVICE TO DOWNTOWN LOWELL: In 1959, the Massachusetts Department of Public Works (MassDPW) began work on the Lowell Connector, a 2.5-mile-long expressway connecting downtown Lowell with the Outer Circumferential Highway (I-495) and the Northwest Expressway (US 3). The $8 million expressway project was built as part of the I-495 contract through Chelmsford. It included the improvement of arterial streets leading to the Lowell Connector, relocation of River Meadow Brook, and the construction of an adjacent water purification plant.
This photo shows the October 24, 1962 dedication of the Lowell Connector at its northern terminus (EXITS 5A-5B-5C). Although records from its opening do not specify its designation, the Lowell Connector had the Business Spur I-495 (“green 495”) designation during the 1960’s and 1970’s. (Photo by Massachusetts Department of Public Works.)
Learn more here: http://www.bostonroads.com/roads/lowell/