Gruta Casa de Pedra or the House of Stone Cave is a cave located in the Alto Ribeira Tourist State park, Brazil. It is 1.8 miles long and has the largest cave mouth in the world, which is 564.304 ft high. The complex of caves were formed thousands of years ago.
The Gruta Casa de Pedra is a limestone cave, with a river flowing through it. Obviously, it has a lot of speleothems. The curtains and columns of stalactites and stalagmites give the cave otherworldly beauty.
Also, other interesting geological formations, such as the pulpit and the royal chandelier in one of the halls, give the cave a fascinating charm. The fauna and flora of the cave also enchants visitors. It has some openings, where it is possible for an ambient light to enter.
Also, there are lighted points, so it’s easier to appreciate some of the main limestone formations. The tunnels of the caves have more than 1300 ft of extension and five enormous halls.
According to unusualplaces.org