Reducción de Santa María la Mayor

The Reducción de Santa María la Mayor is the archaeological remains of a Jesuit mission settlement in Misiones Province, Argentina, associated with the Jesuit reductions established among the Guaraní. The site is part of the set of mission ruins in the region recognised for their cultural and architectural significance.

Visitors encounter masonry ruins of a central church, a formal plaza and surrounding domestic and craft areas that reflect the organized layout imposed by the Jesuits. The surviving stonework and spatial arrangement are typical of 17th- and 18th-century mission settlements in the region.

The reduction was set up and built by Jesuit missionaries working with local Guaraní communities during the colonial period; like other missions in the area it was abandoned after the expulsion of the Jesuits in the 18th century and fell into ruin. Subsequent preservation and archaeological documentation have focused on the church façade, plaza and household foundations.

The site lies in Misiones Province in northeast Argentina amid subtropical forest and farmland; it is one of several mission ruins scattered across the province that are visited together as cultural heritage sites.

• World Heritage status: Inscribed as part of the Jesuit Missions of the Guaranis World Heritage listing, which groups several colonial-era mission sites in the region.

What to See#

• Church and central plaza ruins: Ruined church building and stone façade that formed the religious centre of the reduction, with adjacent masonry foundations of community buildings and workshops.
• Residential and workshop areas: Foundations and outlines of domestic and craft buildings that once surrounded the plaza, showing the planned layout typical of Jesuit reductions.