First time ever offered, this extraordinary one-owner custom home showcases a rare combination of architectural design, privacy, and waterfront living on the scenic Thornapple River -- complete with private island ownership. With more than 140 feet of river frontage and nearly 460 feet of cumulative waterfront including the island, the setting is truly unmatched. Designed to capture the beauty of its surroundings, the home features dramatic floor-to-ceiling windows that frame breathtaking river and island views while filling the interior with natural light. The open-concept layout seamlessly connects the living room, kitchen, dining area, and loft, creating an ideal space for both everyday living and entertaining. A stunning full-height stone fireplace anchors the main living space with warmth and character. Expansive outdoor decking extends the living area and provides multiple spaces to relax, entertain, and enjoy the peaceful waterfront setting. The spacious primary suite is a private retreat featuring additional stonework, a fireplace, private deck access, walk-in closet, and spa-like bath with dual vanities, soaking tub overlooking the river, and separate shower. A library or home office is conveniently located adjacent to the suite. The main level also includes laundry and a guest bath. The walkout lower level offers exceptional additional living space, including a large family room with fireplace, built-ins, and wet bar. Bedrooms two and three each feature attached full baths. Just off the family room, a four-season room with sunken hot tub connects to a screened porch for year-round enjoyment. Located near Ada Park and extensive bike paths, the property offers convenient access to dining, shopping, and recreation in downtown Ada, along with award-winning Forest Hills Schools. The Thornapple River provides miles of all-sports boating, making this an exceptional opportunity to own a truly one-of-a-kind waterfront estate.