luxury houses for sale Jefferson County, United States

Welcome to Sylvan Island, a rare and beautifully restored retreat in the heart of the Thousand Islands where history, luxury, and waterfront living come together. Completely renovated by respected local architects and builders, this historic island property has been transformed into a turnkey masterpiece, ready for its next owner to enjoy from day one. Just a short boat ride from Alexandria Bay, the island offers exceptional privacy, protected deep-water docking, and breathtaking 360-degree views of the St. Lawrence River, including the shipping channel, passing boats, and spectacular Canadian sunsets. Inside, the home features four bedrooms and four bathrooms, all finished with impeccable attention to detail. Large new windows frame water views from nearly every room, filling the home with natural light and creating a constant connection to the river. Wake to the sound of loons calling and water gently lapping against the granite shoreline. Designed for both entertaining and relaxation, the home offers two spacious living rooms and a stunning open-concept gathering space anchored by a stone fireplace and chef-inspired kitchen. Two screened porches provide distinct outdoor living experiences—one overlooking the channel and the other perfectly positioned for sunset views. After a day on the water, relax in the hot tub, unwind in the sauna, or climb to the charming cupola tower for panoramic views that stretch for miles across the Thousand Islands. The protected harbor and generous docking accommodate multiple boats, while the connecting island provides opportunities for future expansion, recreation, and exploration. Every aspect of the renovation was thoughtfully executed, from the all-new windows to the custom finishes throughout, blending timeless island character with modern comfort and convenience. Whether hosting family and friends, enjoying peaceful mornings on the porch, or gathering around the fireplace after a day on the river, Sylvan Island offers an unforgettable lifestyle. Move-in ready and requiring absolutely nothing, this exceptional property is a rare opportunity to own one of the Thousand Islands' most impressive private island retreats.

Set along the majestic St. Lawrence River, this property offers the rare blend of effortless mainland living and the magic of the Thousand Islands lifestyle. Properties in this coveted location are rarely offered for sale, making this a truly special opportunity to own a slice of riverfront paradise with breathtaking views stretching both up and down the river and across to Round Island. From sunrise coffee to unforgettable sunset evenings, this home is designed to capture the beauty of waterfront living at every turn. Guests and family alike will be drawn to the spacious living room, where large windows frame the sparkling river and create the perfect setting for relaxing, entertaining, and gathering after a day on the water. Beautifully updated for comfortable year-round living, the home features a newly renovated kitchen and bathrooms, new carpeting throughout, central air conditioning, and the security of a full-house generator. The flexible floor plan includes a convenient main-floor bedroom along with three additional bedrooms upstairs, offering space for family and visitors alike. Outside, the property continues to impress with a large backyard ideal for lawn games, gatherings, and summer celebrations. A spacious riverside deck invites outdoor dining and quiet evenings overlooking the water, while the protected 180-foot dock provides exceptional boating access for cruising, fishing, and island adventures. The shoreline is enhanced by a beautiful stone retaining wall, adding both character and functionality to this remarkable waterfront setting. Additional features include a detached garage with workshop space, perfect for hobbies, storage, or boating gear. This is more than a home — it’s an opportunity to become part of one of the Thousand Islands’ most treasured riverfront settings, where stunning sunsets, protected waterfront, and generations of memories await.

Imagine arriving at your own private retreat on Grindstone Island, where 480 feet of stunning pink granite shoreline wrap around 2.3 acres of peaceful waterfront. Tucked away in a protected deep-water setting, this property offers exceptional privacy, generous docking options, and the kind of waterfront lifestyle that draws families to the Thousand Islands generation after generation. Begin your mornings with coffee on the expansive waterfront deck as the river comes alive around you. Spend the day boating, swimming, fishing, or exploring all that Grindstone Island has to offer, then return home to gather with family and friends for sunset barbecues overlooking the water. Inside, the cottage welcomes you with cathedral ceilings, natural wood accents, and French doors that frame beautiful waterfront views. Open living space flows effortlessly to the expansive deck that spans the rear of the home, creating seamless indoor-outdoor living. A loft adds character and additional sleeping or recreational space, while two bedrooms and two full baths provide comfortable accommodations for family and guests. First-floor laundry, a UV water treatment system, and a mini-split system extend the enjoyment of the property well into the spring and fall seasons. A garage provides storage for vehicles, recreational equipment, and all the essentials needed for island living while allowing you to explore the island's road network and all that Grindstone Island has to offer. The property is being offered fully furnished and sold as-is, allowing the next owner to begin enjoying the Thousand Islands lifestyle from day one. For buyers seeking a truly unique riverfront compound, the adjacent channel-side property on 1 acre is also available for purchase (MLS #S1564645), creating a rare opportunity to own an expanded family estate with frontage on both sides and unmatched flexibility for future generations. Whether you're searching for a seasonal getaway, a family gathering place, or a private waterfront legacy property, this Grindstone Island retreat offers the perfect setting to create lasting Thousand Islands memories while enjoying spectacular sunsets over the St. Lawrence River.

Welcome to Granite Point—an exceptionally well-built, year-round estate on sought-after Grindstone Island. Constructed in 2022 with an uncompromising focus on quality, durability, and long-term performance, this property offers a rare opportunity to own a nearly new, expertly crafted waterfront home at an incredible value in the Thousand Islands. Set on 8.2 private wooded acres with access to the island road network, the offering includes a 4,235 SF main residence, two barns, and 520 feet of prime waterfront with sweeping views of Canadian provincial park islands and award-winning sunsets—just moments from Canoe Point State Park and Grindstone Winery. Built to last in a river environment, the home features HardiePlank siding, metal/asphalt roofing, energy-efficient windows, and high-performance systems designed for year-round comfort and low maintenance. With 10’ ceilings throughout and exceptional attention to detail, the residence offers both scale and craftsmanship rarely found at this price point. Inside, the home offers 5 bedrooms (3 ensuite, including a first-floor suite) and 5.5 baths with custom cabinetry and tilework. The kitchen is designed for entertaining, featuring dual SubZero refrigerator/freezers, two dishwashers, dual sinks, soapstone counters, inset cabinetry, a walk-in pantry, and premium appliances including a Viking propane range, electric wall oven, Miele speed oven, warming drawer, and built-in ice maker. Living spaces include a great room, formal dining room, and den with gas fireplace, along with a dual wood/gas fireplace. Systems include two high-efficiency heat pumps, central air, circulating hot water, whole-house stereo, motorized shades, Starlink internet, and exterior security. The Red Barn (28x60) includes a guest apartment, while the Gray Barn (26x36) offers storage, workshop space, and loft. Outdoor living features an ipe deck, covered porches, and dockage for four boats—perfect for enjoying the award-winning sunsets. Supported by well, septic, and a buried propane tank. A rare blend of new construction, superior build quality, and prime Grindstone Island location—Granite Point is a true legacy property

Discover the perfect canvas for your island retreat with this charming summer cottage studio on picturesque Grindstone Island. Set on approximately 1+ acre with 200 feet of deep-water frontage, this property offers stunning channel views and an ideal setting for your seasonal escape. A new deed is in process to reflect the updated acreage and waterfront; a full survey is complete and available. The studio features all-new windows that frame serene waterfront vistas, a well-insulated floor, and room to expand. Inside, a full bathroom is underway with a shower already installed and the toilet and vanity on site, ready for completion. The property is equipped with a 1000-gallon septic system, brand-new electric service with underground power, and all PEX plumbing already in place—providing a strong foundation for your finishing touches. Enjoy immediate boating access with underwater anchors ready to secure the included 26' x 8' floating dock. In addition, a dock in Rusho Bay will be available for your use while new dock is built, offering convenient temporary access to the island. Whether you're looking to finish it yourself or bring in a contractor, this studio offers the rare opportunity to create a custom island escape with privacy, incredible views, and room to expand with trail access to all that Grindstone Island has to offer.