The western state of Colorado, nicknamed the "Centennial State," is bordered by Arizona, Nebraska, New Mexico, Oklahoma, Kansas, Wyoming, and Utah.

Arapaho National Wildlife Refuge is one of six national wildlife refuges managed by the U.S. Fish and Wildlife Service in Colorado. Other Federal managers of land in Colorado include the Bureau of Indian Affairs, Bureau of Land Management, Bureau of Reclamation, Department of Defense, National Park Service, and the U.S. Forest Service.

Water is an important resource for Colorado's ecosystems. The major river basins of Colorado, as described by the USGS National Water Information System, include the Arkansas River Basin, Colorado River Basin, Platte River Basin, and Rio Grande River Basin.

• To find out about animals and plants of the Southwest, many of which are distributed throughout Colorado, visit the SWIN Animals and Plants of the Region page.
• To find out more about regional issues such as wildlife disease, invasive species, fire, and water and drought, including links to state-specific resources, visit the SWIN Regional Themes page.
• To find out about geospatial products, databases, and other information for Colorado and the Southwest, visit the SWIN Live Maps and Data page.