I feel like a lot of people I met from western Mass considered Worcester eastern Mass, and a lot of people from eastern Mass consider Worcester western Mass. While this doesn't answer the question exactly, I like to think that the border is some nebulous gray area surrounding Worcester.
imawerechicken t1_j0tk9q5 wrote
Reply to Where does Western Mass begin to you? by Elegant-Anteater783
I feel like a lot of people I met from western Mass considered Worcester eastern Mass, and a lot of people from eastern Mass consider Worcester western Mass. While this doesn't answer the question exactly, I like to think that the border is some nebulous gray area surrounding Worcester.