Marienkirche Erfurt, Weimar & Thuringia

Thuringia’s second-largest church (after the Dom in Erfurt, also dedicated to Mary), the striking, five-naved, 14th-century Gothic Marienkirche was desanctified in 1975. It's now used as a memorial museum to Thomas Müntzer, who preached here to his rebel followers before the disastrous Schlachtberg battle of the 1524–25 Peasants' War.