CT line in Southwick to NH line in Northfield via Westfield, Northampton, and Greenfield.

Cosigned with US 202 to Westfield.
Cosigned with US 5 from Northampton to Bernardston. Picks up MA 116 briefly in Deerfield.
Cosigned with MA 63 in Bernardston.

Originally NE-10. Spends very little time by itself in the state.

Within 5 towns of the CT border, MA-10 has hit each of the four cardinal directions in town names: Southwick, Westfield, Easthampton and Northampton.

Kurumi’s CT 10 entry.
Dan Vincent’s MA 10 page.