Bow your head, say a prayer and perhaps even light a candle in Nossa Senhora do Pilar Cathedral. This important place of worship may not be open 24/7, so check ahead for hours if you'd like to go inside.
You'll find this principal church in Sao Joao del Rei Centro. Once you've done everything you want to at Nossa Senhora do Pilar Cathedral, take a look at nearby Forras Square, Holy Trinity Church, and Saint Francis of Assisi Church.