Gruta Casa de Pedra in Brazil has the largest cave mouth in the world – it is higher than the Great Pyramid of Giza. But the largest cave chamber in the world is larger still.
The enormous cave mouth pictured above is 172 metres high. You could fit the Statue of Liberty into that space nearly four times, and it is higher than the Great Pyramid of Giza. It’s known as Gruta Casa de Pedra, the “cave house of stone.” You can find this huge opening in Alto Ribeira Tourist State Park, near São Paulo in Brazil. The cave itself stretches back several kilometres, but the interior never really rivals the immensity of the entrance.
To find the largest chamber within a cave system, you have to look to Asia. In 1981 cavers in Borneo (the Malaysian portion) were exploring a cave called Gua Nasib Bagus, the “good luck cave.” Within, they found a chamber 600 metres long, more than 400 metres wide, and 115 metres high. To really get a handle on how large that is, consider the fact that the Great Pyramid of Giza is 220 metres wide and 138 metres high. All but the top 23 metres, the top sixth of the pyramid, would fit inside this one chamber.
That chamber, called the Sarawak Chamber, held the record for largest known cave interior – both by area and by volume – for eight years. Then, in 1989, cavers in China discovered a rival: the Miao Room. It has a narrower base, 852 metres long and 191 metres wide, but its total volume is even larger than the Sarawak Chamber. The Miao Room has a volume of 10,780,000 cubic metres – the same volume as more than four thousand Olympic-size swimming pools.
You can see some photos and a visualisation of the Miao Room here: