- McCook is a small city located in Red Willow County, Nebraska, United States. It has a population of approximately 7,500 people. The city was named after General Alexander McDowell McCook, a Union Army officer during the American Civil War. McCook is known for its historic downtown district, cultural events, and outdoor recreational opportunities. Some of the popular attractions in the area include the Senator George W. Norris State Historical Site, Red Willow State Recreation Area, and the Fox Theatre.