The Mission was filmed in Argentina and in the United Kingdom.
Fort Amherst
In movie
Scene where Rodrigo Mendoza is being held in the monastery after he had murdered his brother.
Real
Scene was shot Fort Amherst was originally built in 1755, containing a labyrinth of underground tunnels and hidden gun positions, to improve the defense of the River Medway.
Chatham
Iguazu Falls - Island San Martin
In movie
Scene where Father Gabriel sees the task that is ahead of him and climbs the waterfall.
Real
Scene was shot Iguazu means Great Water in the Guarani language. It is an appropriate name for the river that travels 1,300 miles through Brazil and ends in wonderful falls in the jungle. That place connects the borders of Brazil, Argentina and Paraguay.