Set within Bernardsville's coveted "On The Mountain" enclave, this extraordinary residence is a rare offering steeped in architectural history and timeless charm. Originally the carriage house of famed 19th and 20th century architect George B. Post Sr.'s estate, this expanded and converted 1890s home rests on over 5 private acres, accessed by a long and winding driveway setting the tone for serenity and seclusion. History echoes throughout the home, where original stonework, century-old trees, and plantings create a rich sense of place. It beautifully balances traditional authenticity with modern elegance, offering warmth, character, and charm at every turn. At the heart of the home is a dramatic living room, offering an inviting space for both grand entertaining and quiet reflection. With over 5,000 square feet of living space and following an substantial addition, the home features five bedrooms and five full bathrooms, including a private guest suite. Outdoor living is equally compelling with seasonal views of the Somerset Hills, inground pool, and eight garage spaces for the car enthusiast, a truly rare amenity. Located just minutes from the NJT rail to NYC, shopping the the Somerset Hills Country Club, this one-of-a-kind property rewards its next Owner with a remarkable lifestyle where architectural pedigree, natural beauty, and peaceful living converge. A legacy property and a rare opportunity.