Secluded Gem in Blue Ribbon Mount Sinai School District! Discover an exceptional living experience at 3 Heidi Lane, a stunning Colonial-style residence privately nestled at the end of a serene cul-de-sac in desirable Mount Sinai. Perfectly placed on just under an acre, this property offers unrivaled privacy, with one side extending into state owned land, creating a tranquil and natural buffer offering seclusion from neighbors. Inside you will find a spacious and inviting layout featuring 4 bedrooms and 3.5 bathrooms, including a coveted first floor master bedroom suite (with Jacuzzi tub) for added comfort and convenience. The heart of the home is an entertainer’s dream—a wide open floor plan on the main level, including a huge living room, eat in kitchen, formal dining room and library, making it ideal for hosting gatherings both large and small. A distinct separate guest wing with separate entrance ensures ample space and comfort for visitors, or offers an ideal setup for a home office or creative studio or possible mother-daughter with proper permits, accommodating multi-generational living with ease. Additional highlights include a two-car garage, a huge basement ready for finishing, and a private backyard oasis with scenic views of the Long Island Sound from the top of the hill. Enjoy the serenity of nature, the space to entertain, and the excellence of the Mount Sinai School District—all in one breathtaking property. Don't miss your chance to own this one-of-a-kind private retreat!