Perched above the rolling hills of Millbrook Hunt Country with sweeping Catskill Mountain views, this idyllic retreat and exceptional equestrian estate spans 185 ultra-private acres. Once the beloved property of Margaret Carnegie, only child of Andrew Carnegie, the estate preserves a rich legacy of elegance and prestige. Originally built in 1865, it has been thoughtfully expanded to blend historic grandeur with modern luxury. The main residence offers timeless refinement, including a paneled library with fireplace, an elegant dining room that seats 30, and a grand living room with soaring ceilings and French doors opening to a sunset terrace overlooking the Catskills. At the heart of the estate is a world-class equestrian facility designed by renowned French architect Atelier Choiseul, featuring state-of-the-art stables, paddocks, a tack room, staff housing, and a sophisticated lounge, along with a hunter trial course. Miles of fenced pastures, private riding trails, ponds, and serene landscapes sit just minutes from the village of Millbrook and within 90 minutes of Manhattan. The vast acreage provides a quintessential pastoral experience and room for additional recreational or residential expansion. With its privacy, history, and unmatched amenities, this is a rare legacy property offering the finest expression of Hudson Valley luxury.