More than 3.5 million people visit a sandy, hilly area called Indiana Dunes each year. It sits along the shores of Lake Michigan, about southeast of Chicago. Visitors to the area swim and sail on the lake. They watch birds in the wetlands. They study plant life in the forests of oak and maple trees. Now, the 6,000-hectare site is the newest national park, and also 61st national park in the United States. It became Indiana Dunes National Park on February 15, 2019.