History
Weird and wonderful history of Brimham Rocks
The rock shapes at Brimham are fascinating and unique
People believed that the rocks had been man-made. Carved out of the stone hundreds of years ago by pre-historic men, perhaps in a similar way to how Stonehenge had been built. Geologists now know that the rocks at Brimham have been made by entirely natural processes, over millions of years.
Brimham’s rocks are mainly made out of Millstone Grit. 430 to 380 million years ago, a vast range of mountains as big as the Himalayas lay to the north. These were thrown up when what is now North America collided with Europe. Mighty rivers washed loose sand, grit and pebbles down from these mountains and flowed into a delta covering half of Yorkshire. As the water slowed down in the delta, the grit and mud settled on the river beds. The grit included crystals of steel-hard quartz and softer crystals of feldspar. Over the millennia these layers compressed and hardened to form layers of rock.
The unusual shaping of the rocks happened far more recently, during the last Ice Age. Some 18,000 years ago, an ice cap covered the northern Pennines. At times, part of the rock bed stood out above the ice, exposed to fierce winds blowing off the ice cap and carrying tiny particles of ice, sand and other debris. The rocks were sandblasted into new shapes, particularly at ground level where the winds were strongest.
It is only over the last two hundred years that people have really come to understand how they were made. So come and see for yourself and let us know what you think.