The Nova Iguaçu Volcano is located in the state of Rio de Janeiro, Brazil, in an area of volcanic rocks at the north-eastern border of the Mendanha massif. Klein and Vieira proposed the site to be an extinct volcano with a volcanic cone, volcanic crater, and volcanic bomb. Scientific journals have studied the volcanic geology of the area, identifying the rocks of volcanic appearance as constituted of subvolcanic intrusive rock bodies. The Nova Iguaçu volcano theory is now extinct in academic communities, but the myth continues in sightseeing promotion groups.
Recent research revealed that volcanic eruptions did occur in the Nova Iguaçu region. After the eruptions, an intense uplifting and consequent regional denudation took place.
Coordinates -22°47'9.347" N -43°29'54.352" E