Mariana's colonial heart is small enough to walk in a morning. The Praça Minas Gerais anchors the centre with its matched pair of Baroque churches and old town hall, while the Cathedral da Sé a few blocks away holds a pipe organ from 1701 and a remarkable collection of sacred art. Beyond the squares, the Mina da Passagem gold mine just outside town is one of the most accessible old mines in Minas Gerais.