The segment of the Taconic Mountains in Massachusetts is often considered a part of the Berkshires, although they are geologically separate and are a comparatively narrow range along New York's eastern border.

Sir Francis Bernard, the royal governor (in office 1760–1769), named the area "Berkshire" to honor his home county in England.

Geologically and physically, the Berkshires are the southern continuation of the Green Mountains of Vermont, distinct from them only by their lower average elevation and by virtue of what side of the border they fall on.

In Connecticut, where they are referred to as the Litchfield Hills, they extend east from the upper Housatonic River valley in the northwest part of the state.

They are on the average 1,000 ft (300 m) lower and less prominent than the Green Mountains of Vermont, and form a broad, dissected plateau punctuated by hills and peaks and cut by river valleys.

Much of the Hoosic and Housatonic River valleys have underlying bedrock limestone and marble which contribute to calcareous wetlands unique in Massachusetts.

Combined with the rich mesic forests ranging from the northern hardwood to the taiga or sub-alpine, the Berkshires have a valuable, biologically diverse ecosystem.

Today, efforts are being made by many organizations to preserve and manage this region for biological diversity and sustainable human development.

[7] The Berkshires have numerous shops, motels, hotels, museums, and trails,[8][9] including part of the Appalachian Trail, large tracts of wilderness and parks Berkshire Botanical Garden and Hebert Arboretum The area includes Bash Bish Falls, the tallest waterfall in Massachusetts.