The Iglesia San Buenaventura is one of the great surviving colonial churches of South America. The exterior is deceptively simple — low, wide, with wide wooden galleries running along three sides to shelter the walls from tropical rain. A separate wooden bell tower stands nearby in the old Guaraní mission style. None of this prepares you for what is inside.
The interior is a masterpiece of Guaraní baroque: every wooden surface — ceiling, columns, pulpit, altarpiece — is carved and painted in a style that blends Spanish Baroque forms with indigenous Guaraní imagination. The hexagonal pulpit, supported by a carved giant's head and surmounted by a dove, is particularly extraordinary. The high panelled ceiling is painted in deep reds, ochres, and golds. Entry is free; morning light is best. On the UNESCO tentative list for World Heritage designation.