Own the entire block! 9 Mansfield Avenue offers a unique 0.7-acre “island” parcel with zero shared property lines in the heart of the Marstons Mills Lake District. This self-contained sanctuary is bounded by quiet village ways and a lush perimeter of mature maples, hydrangeas, azaleas, and rhododendrons. The spacious interior features a kitchen with maple cabinets, granite counters, and a tumbled marble backsplash. Sliders open to a sweeping, semicircular mahogany deck where you can survey your grounds and the shimmering waters of Shubael Pond. A classic Dutch door leads to a light-filled breezeway, a lower grilling patio, and an oversized garage with a cedar closet. Enjoy first-floor living with a primary bedroom, full bath, den, and living room centered on a wood fireplace. Three more bedrooms and a second bath are upstairs. With a brand-new 4-bedroom septic system, this distinctive home is close to shopping, dining, and is just one mile from the Olde Barnstable Golf Course!