19 Greentree Lane Set behind a gated entrance with a private guard house and unfolding across 8.4 private acres, The Retreat at Greentree is a true estate in every sense, engineered for privacy, designed for lifestyle, and positioned as one of the most unique offerings in the Hudson Valley. A cascading waterfall greets you on arrival, establishing a sense of calm and separation from the outside world. From that moment forward, every detail reinforces the same idea. This property was built intentionally, without compromise. Originally designed by renowned architect Paul Rudolph, the residence carries a level of architectural pedigree rarely available. Spanning over 7, 750 square feet, the home blends that design legacy with modern performance, including radiant heated floors, geothermal systems, and thoughtfully curated living spaces that feel both refined and highly functional. What truly sets this property apart is the lifestyle it delivers. A private helipad offers direct access to Manhattan in approximately 14 minutes, redefining convenience at the highest level. The grounds unfold as a resort-caliber setting, anchored by a heated saltwater pool, three private cabanas, and a fully equipped outdoor kitchen with a dedicated dining space designed for effortless indoor outdoor living. A rare white sand beach introduces an unexpected element, creating a setting that feels more like a destination resort than a private residence. Inside, the home takes on a spa-like atmosphere, with wellness-driven features including a private sauna and spaces designed to restore and recharge. The primary suite is its own retreat, complete with a three-season room that extends the experience outdoors while maintaining complete privacy. A fully built-out home theater adds another layer to the lifestyle, bringing a true cinematic environment into the comfort of your own home. Beyond the property itself, the location adds another dimension. This is the perfect getaway for winter weekends, fall retreats, or summer escapes, surrounded by some of the Hudson Valley's most sought-after destinations. Just minutes from LEGOLAND New York Resort, Woodbury Common Premium Outlets, Warwick Valley Winery & Distillery, local apple orchards throughout Warwick, Bear Mountain State Park for skiing and outdoor recreation, and the five-star Glenmere Mansion, the area offers a rare blend of recreation, luxury, and accessibility. Hiking, camping, fishing, skiing, biking, horseback riding, fine dining, and shopping are all within reach, creating a year-round lifestyle that is both active and refined. This is more than a residence. It is a fully realized compound, private, efficient, and architecturally significant, built for someone who values time, discretion, and a level of living that cannot be replicated.