On the coveted backshore of Cousins Island, this extraordinary deepwater estate captures a rare vision of coastal Maine living. Designed by noted architect Joe Waltman and masterfully built by Anastos & Nadeau, the residence is perfectly positioned to embrace sweeping southern views across Casco Bay toward the Portland skyline, with deepwater access, private dock, mooring, and sandy beach offering an exceptional boating lifestyle. Classic shingle-style architecture, soaring 10-foot and 25-foot ceilings, and walls of glass create a home that feels both grand and welcoming. Brazilian cherry and natural stone floors, custom millwork, crown molding, built-ins, and an open interior balcony add warmth and craftsmanship throughout. The living and family rooms flow seamlessly together, framed by expansive water views and designed for both quiet evenings and effortless entertaining. The kitchen and dining area feature a substantial island, professional-grade appliances, dual wall ovens, walk-in pantry, wet bar alcove, and generous dining space overlooking the bay. A private den and first-floor office offer additional flexibility. Upstairs, the primary suite serves as a peaceful retreat with a reading nook overlooking the water, walk-in closets, and a marble bath with soaking tub and walk-in shower. Three additional bedrooms, full bath, laundry room, and a daylight lower level provide flexible space for guests, recreation, or fitness. Outdoor living is equally compelling with an expansive Ipe deck and sun-filled stone patio overlooking the shoreline. Though the setting feels private and serene, the property is just minutes from Yarmouth Village, Portland, marinas, restaurants, and some of Maine's most desirable coastal communities. A rare opportunity to own a remarkable waterfront estate combining architectural pedigree, deepwater access, and the enduring beauty of Casco Bay.