By the 1920s, after nearly a century of heavy commercial use, the waterfront which had supported the community for generations had fallen into decay. The village decided to purchase the land along the harbor and created Northport Memorial Park in 1932, which is a defining feature of Northport today.
In 1967, the Long Island Lighting Company (LILCO) opened the Northport Power Station, currently the largest oil-fired electric generating station on the East Coast. The four enormous stacks are a well-known landmark that can be seen from as far away as Connecticut across Long Island Sound. Each stack is 600 feet (180 m) tall.
The Northport Trolley which had ceased operations in 1924 enjoyed a popular revival in the 1970s and 1980s, transporting weekend tourists along Main Street. Unlike the original electric trolleys, this nostalgic replica was horse driven. It also ran on rubber automobile tires rather than utilizing the original rails which still remain a visible element of Main Street to this day.
In July 1984, Northport garnered nationwide media attention for being the site of the gruesome murder of 17-year-old Gary Lauwers by his friend, high school dropout and alleged devil-worshiper Ricky Kasso The events made national headlines and have since been recounted in books and movies, which caused the village to suffer a negative reputation for reputed satanism.
Every September the village of Northport commemorates its rich history with the celebration of Cow Harbor Day, which follows the annual Great Cow Harbor 10K race.