Obvious alignment changes

[PHLBOS]

Canton, MA:
Green Lodge St. west of the I-95 interchange (w/I-93 (US 1/MA 128)); old, abandoned alignment to the left.
Prior to the interchange being built in the mid-60s; Green Lodge St. ran straight.  No traces of the old alignment east of the interchange remain.

Danvers, MA:
MA 35/Water Street facing southbound, remants of the old, sharper S turn alignment to the right.
Road was re-aligned (for a more gradual turn) and bridge was replaced in 1980.

[Chris19001]

In SE PA, we have a bunch.  Mostly they were for ancient roadbeds that outgrew their traffic limitations.  Bethlehem Pike (today's PA-309 in places) has two of the easier examples to illustrate, as several old alignments are still paved (although not continuous anymore). 

Below is in Center Valley, PA, where the old alignment was slightly to the west and follows 309 north, until it intersected the town grid at an entirely different direction and left modern day 309's routing (becoming PA378 instead)
https://www.google.com/maps/@40.5244895,-75.3888186,842m/data=!3m1!1e3

This one is in Line Lexington, PA and just parallels to the west before its intersection with Hilltown Pike.
https://www.google.com/maps/@40.2845435,-75.2610555,1035m/data=!3m1!1e3