You'll probably see Our Lady of the Assumption Cathedral across town before you actually find this incredible place of worship. Peek inside if the doors are open or just take in the facade from the street.
When you've finished up at this principal church in Barbacena, why not make your way to Andradas Square, Minas Gerais State University, and Barbacena Municipal Museum? They're not very far from Our Lady of the Assumption Cathedral and also a hit with travelers.