Beneath the Atlantic Ocean.

Scientists believe nature began to slowly craft Howe Caverns some six million years ago - long before even the ancient, extinct animal known as the woolly mammoth appeared on Earth. The caverns are unique for more than their age and beauty - they are among a very small number of mineral caves in the world.

In those long-ago, early days, the eastern part of New York State was covered by an arm of the Atlantic Ocean. The waters of this sea swarmed with life: corals, sponges and many creatures similar to oysters, clams and snails were all plentiful. Many of these creatures built their shells from calcium carbonate, which they gathered from the waters around them. Generation after generation of these creatures lived and died in their watery home. And - very slowly - the bottom of the sea became covered with hundreds of feet of the creatures' empty shells and fine particles of dirt.

At first, these deposits were very soft. But as layer upon layer of new deposits fell to the sea bottom, the pressure built up. Finally, the lower layers were pressed into a type of rock called limestone. Millions more years passed, and the continent of North America began to rise slowly out of the sea. This was during the Cretaceous period of Earth's early history, some 65-136 million years ago. As the sea water drained from the rising mass of rock, a brave new land began to form. Hence, the beginning of a remarkable era. Rain fell gently upon the new land. While much of this rain water drained away in brooks and rivers, a great deal of it soaked into the ground, just as it does today during a cloudburst.

Most people think of water as a very "soft" substance: you can plunge your hand into a tub filled with water, and it won't really hurt (If you try the same thing with a tubful of rocks, on the other hand, it will hurt.). But as soft as water seems, its motion and movement - no matter how slow - can have a powerful effect on even very hard rocks over a long period of time. Because the limestone beds laid down by the sea creatures were softer than many rock formations (such as marble or granite), the rain water trickling down from the ground above soon began to erode the top layers. Small cracks opened up to the layers below, and the rain water dissolved its way through them, too. In time, the small cracks grew to be large cracks through which underground streams flowed. And that is how the great cave formations and winding passageways of Howe Caverns were formed: over the course of millions of years, underground brooks and streams gently carved them out of the solid limestone deposits left behind by sea creatures eons before.