Welcome to 121 Old Field Rd, Huntington-a rare opportunity in Harborfields School District, perfectly situated on a magnificent .80-acre level property. This private, fully fenced oasis features a 20' x 40' heated in-ground pool with a 2-year-old liner, robot cleaner, and a separate oil tank dedicated to pool heating. Entertain effortlessly with two spacious decks, a beautiful paver patio, and a storage shed surrounded by lush, park-like grounds. Inside, this expansive 5-bedroom, 3.5-bath split-level home offers an ideal layout for comfortable living and entertaining. The granite eat-in kitchen boasts all-new stainless steel Frigidaire appliances, while the formal dining room and inviting living room with a classic brick fireplace create warm, welcoming gathering spaces. Hardwood floors, generous room sizes, abundant storage, and a two-car garage complete the main residence. The primary suite features its own ensuite bath, accompanied by additional spacious bedrooms and beautifully maintained baths throughout. A standout feature is the legal accessory apartment, offering exceptional flexibility for rental income or multigenerational living. Complete with its own private entrance, updated kitchen and bath with laundry, bedroom, separate utilities, living rm with brick fireplace, bonus room, and full attic, this permitted apartment provides tremendous value and versatility. Additional updates include a new skylight, newer roof improvements, and eight individual air-conditioning units for customized comfort throughout the home. Ideally located in a prime Huntington location, you'll enjoy everything this vibrant community has to offer, including exceptional restaurants, exciting nightlife, beautiful Heckscher Park, stunning beaches, the renowned The Paramount, boutique shopping, and charming local eateries. Commuters will appreciate being just minutes from the Long Island Rail Road, providing convenient service to both Penn Station and Grand Central Station, while also enjoying close proximity to the waterfront communities of Cold Spring Harbor, Lloyd Harbor, Centerport and Northport. This exceptional property offers the perfect combination of space, versatility, and location-an outstanding opportunity to enjoy the very best of Huntington living.