The Gruta Rei do Mato (MG-3653) is a cave located at the edge of the BR-040 highway, close to the off ramp to the city of Sete Lagoas, in Minas Gerais, Brazil.

From Sete Lagoas the cave can easily be reached by bus, taxi or car.

Gruta Rei do Mato means "Cave of the Forest King" in Portuguese.

The area around Sete Lagoas has many cave systems, of which the Gruta Rei do Mato is the most widely known.

In the "Rarities Hall" are nearly identical parallel columns, formed by the calcium carbonate crystals of calcite.