Tucked alongside a harbor on Long Island's north shore, Mount Sinai has long attracted residents and visitors. It was the site of an early European settlement in 1664 and the embarkation point of the Revolutionary War foray into enemy territory by Maj. Benjamin Tallmadge, a member of Gen. George Washington's Setauket spy ring. Mount Sinai was a farming and seafaring community in the 1600s, 1700s, and 1800s. In 1891, it became the site of the "sanitary resort" known as the Crystal Brook Park Association. Later, it drew an early community of artists and photographers who captured the natural...