520 Fair Avenue - a truly rare West Petaluma country property, offered for the first time in over half a century. Privately sited on approximately 1.25 acres, on a secluded flag lot, this hidden retreat is set well back from the street, where a long drive opens to an impressive circular motor court and an expansive single-level residence. Encompassing over 2,300 sq. ft., the home offers 3 spacious bedrooms and 3 full bathrooms, with grand-scale living areas and a seamless, flowing floorplan designed for both refined entertaining and everyday comfort. Recently refreshed with wide-plank luxury vinyl flooring, fresh interior and exterior paint, and a brand-new heating and air conditioning system with updated ducting, the home blends timeless character with modern ease. At the heart of the home, the expansive kitchen is appointed with new quartz countertops, updated appliances, and a distinctive built-in brick BBQ, opening directly to a large family room with vaulted ceilings, a built-in wet bar, and sliding doors that lead to the backyard patio creating a natural connection to the outdoors and effortless indoor-outdoor living. Several bedrooms feature custom built-in cabinetry, adding both charm and functionality. Just beyond the kitchen, a generously sized mudroom and laundry space offers exceptional utility, with direct access to the oversized 3 car garage, a door to the backyard, and a conveniently located full bathroom. The grounds are nothing short of exceptional - over an acre of park-like privacy framed by majestic heritage oaks. A generous backyard patio and a charming cabana offer both covered and enclosed spaces for year-round enjoyment. The setting evokes a peaceful, country estate while remaining just minutes from the vibrancy of downtown Petaluma. A rare blend of scale, seclusion, and modern comfort in one of West Petaluma's most coveted settings.