Colorado became the 38th state of the United States on August 1, 1876. Known as the "Centennial State" because it joined the Union during the nation's 100th anniversary, Colorado is famous for its stunning Rocky Mountain landscapes, outdoor recreation, and rich natural resources. The state has a diverse history, with indigenous peoples such as the Ute and Cheyenne living in the region long before European settlers arrived. The discovery of gold in the mid-1800s sparked a rush of settlers, and by the time it became a state, Colorado had a booming mining industry. Today, Colorado is known for its progressive politics, vibrant cities like Denver and Boulder, and a strong economy rooted in technology, tourism, and agriculture.