Upstate new York island vacation Grant Island is a little slice of heaving on Brantingham Lake. Brantingham Lake is located on the Southern border of the Adirondacks in New York State. It has approximately a 15 mile circumference and home to a wide array of wildlife. Including the “Grant Island Creatures” See our Instagram for details on the doings of the Grant Island Creatures. ||¬†Upstate new York island vacation