The Glacial Potholes found on the Deerfield River, at the base of Salmon Falls in Shelburne Falls, Massachusetts are a testament to the creative power of geological time, ice and rock. The multitude of otherworldly potholes found here are one of the largest collections of natural potholes in the world and the site of the largest pothole on record.

The story of the Glacial Potholes, known as kettles in geological terms, dates back hundreds of millions of years, most recently taking the form they have today at conclusion of the last “Glacial Age.”

As the glaciers receded, fifty separate “pools” ranging from 6 inches to 39 feet in diameter were formed. The round holes were ground down by granite “by a whirlpool effect of water and gyrating stones of varied sizes.” As a result of the constant whirling of the granite stones, the potholes took on a remarkably symmetrical and round shape. They continue to be formed to this day during the end-of-winter snow melt when water levels rise significantly and the grinding millstones, still found in the smaller potholes, are whipped up into swirling whirlpools.

Located steps away from The Bridge of Flowers, in western Massachusetts, it used to be that a soak in the cool waters of the potholes was a welcome respite on a muggy New England day. However the pools have been “closed” to the public since 2002. Any swimming there is illegal and done at ones own risk.