Route 220 was commissioned in 1936, leading from Route 192 to the Osborn Prison, over the town line on Shaker Road in Somers. By 1938, however, the eastern end had been moved to a more desireable location: the Massachusetts state line. Its length was now 2.90 miles.

In 1960, the state Committee to Reclassify All Public Roads recommended the following changes for the area highway system:

• turn Shaker Road over to the town
• make all of Taylor Road a state highway, from Route 190 to the state line
• make Shaker Road east of Taylor Road a special service route for prison traffic

The above changes would have made Route 220 a north-south road, from Route 190 into Massachusetts. In 1962, what the state did instead is extend Route 191 over Taylor Road to the state line (see map below).

A year later, talks were in place to revise area highways again. Elm Street would be added to the state system, to connect the prisons to I-91; and the portion of Taylor Road south of Shaker Road would revert to the town. On Oct. 7, 1963, Route 220 was resuscitated and extended westward along Shaker Road and Elm Street to US 5. Route 191 reverted to its south-of-Route-190 alignment. The Shaker Road connection to the prison complex became SR 404.

Short-lived extended Route 191 replaced part of Route 220 in the 1963 state highway map.

Alternate Route 190 proposed

In the late 1990s, the Capitol Region Council of Governments initiated a study of Route 190 in Enfield and Somers, to address projected traffic increases on the road. A major widening was ruled out. However, in a December 2000 meeting the idea surfaced to extend Route 220 eastward instead of north, to end at Route 186 or Route 83 in Somers. This way, Route 220 could serve as a northern alternative to Route 190.