Westerly, one of the most important estates on eastern Long Island, is an extraordinary brick Georgian created in 1929 by the renowned firm Hiss & Weekes for the heart of Southampton’s prized estate section. Crowning 15.4 acres of vast meadows and formal gardens beyond privacy gates and hedges, the exquisite 25-room mansion boasts as its showpiece an enormous ballroom and grand terrace that have set the stage for legendary social events of elite members of Southampton and Palm Beach society. The three symmetrical wings boast a soaring marble entrance, Swedish pine library, firelit dining room, full-service gourmet kitchen, and wine cellar. Complementing six second-floor suites is a spectacular owners’ haven. A brick carriage house, tennis court, swimming pool, pavilion, and sunken garden adorn the melodious grounds.