A streetcar stop, located on the surface streets, served a number of routes beginning in 1863, including the Green Line A branch until 1969.

[5][6] A second track was added in 1839, and in 1843 the railroad began offering season fares for around $60, making it one of the first commuter rail systems.

The highway occupied a significant portion of the right-of-way, dropping the Worcester Line from 4 to 2 tracks from Back Bay to Riverside.

The square soon became a transfer point between the Newton Street Railway's expanding suburban system and service into Cambridge and Boston.

Expecting little traffic at the intersection, the streetcar tracks were placed in a contraflow lane, while the platforms were moved to the north side of the rotary in a dedicated median.

However, the rotary proved to be busy and congested, resulting in frequent delays and automobile-streetcar collisions.

[9] Although no longer served by rail transport, Newton Corner remained a transfer point for bus routes.

In 1967, the MBTA began operating express bus routes from Watertown Yard and Oak Square (later extended to Brighton Center) to downtown Boston.

In 1972, the MBTA took over remaining M&B bus service, including six routes that terminated at Newton Corner.

However, a limited version of the proposal was considered wherein the route 71 trolleybus would be extended from Watertown to Newton Corner.

[12] On September 1, 2019, outbound route 502 and 504 buses began turning directly onto Galen Street rather than serving the Newton Corner rotary stops; outbound route 501 and 503 buses began serving the rotary stops at that time.

[13] Most MBTA service began operating on Saturday schedules on March 17, 2020, due to the COVID-19 pandemic.