Kummakivi Balancing Rock: Strange Geological Formation Seemingly Defies Rules of Physics

In a little village called Ruokolahti in Finland, by the country's greatest lake, lies one of the most puzzling remains of the last ice age.

Unusual Balancing Act

An unusual rock formation lies in the middle of the forest of Valtola in Southern Savonia. It features two boulders, one precariously perched on the top of the other. While the upper rock looks like it would roll off any time, this has not happened.

The rock on the bottom is shaped like a carved mound lodged in the earth and has a smooth, convex surface with a very small footprint. Meanwhile, the rock at the top measures 23 feet (7 meters) long and weighs 1.1 million pounds (500,000 kilograms). It is held so firmly that it cannot be rocked by human force.

The giant megalith is also known as Kummakivi, meaning " strange rock" in Finnish. It is also called "the mother of all Finnish stones." The geological formation is a sight to behold, yet it raises many questions regarding its nature.

Some experts believe this site is between 8,000 and 12,000 years old.

The Saimaa Geopark in Finland, recognized by UNICEF as a Global Geopark, suggests that it is approximately 11,500 years old.

Mystery Unveiled

Both local residents and experts tried to find an explanation for how the rock had wound up in such a perplexing position. According to Finnish folklore, the massive balancing rock was left behind by giants and trolls who carried, threw, or rolled them there, but geologists explain the science behind this strange formation.

Physics explains that heavy things do not automatically slide or fall more quickly than light objects. This is considered one of the reasons behind the firm position of the upper rock. Aside from this, coarsely textured, surface-gripping objects can get strong friction to contend with.

Geology also provides explanations for this mysterious phenomenon. The interior of rocks is not necessarily uniform in composition. This means that the density of Kummakivi is not evenly distributed throughout, according to the Wisconsin Geological and Natural History Survey. Rocky interiors are also porous and contain pockets of lower density and space side-by-side clusters of minerals. This means that the center of balance for a stone is not always easily predictable.

Kummakivi is also not the only rock of its type. The world has a sub-category of similar phenomena called "precariously balanced rocks."

In North Yorkshire, England, there is the Druid's Idol, which is even more precisely balanced than Kummakivi. Locals in Tamil Nadu, India, named a similar structure to Krishna's Butterball after the eighth incarnation of the Hindu god Vishnu. There is also the Arches Rock in Arches National Park in Utah.

Scientists explain that such formations have more down-to-earth origins. They could be formed when harder rocks stay behind as softer rocks erode or when retreating glaciers or landslides move them to unusual positions.