The Great Sand Dunes National Park in Colorado, USA, is known for its extensive sand dunes. These dunes are among the tallest in North America and showcase an extraordinary natural landscape formed by the interplay of wind and sand over thousands of years. The park not only features these impressive dunes but also offers diverse ecosystems, from wetlands to alpine forests. Visitors can engage in various recreational activities, like sandboarding and hiking, while learning about the unique geology and cultural history of the area.