Colorado Office of Archaeology and Historic Preservation
- National and state register information including listed properties, nomination forms, deadlines, and ten basic steps to listing property.
- http://www.coloradohistory-oahp.org/

Colorado State Penitentiary
- History of the Colorado State Penitentiary, corrections records, and prisoner index.
- http://www.colorado.gov/dpa/doit/archives/pen/prison.html

Colorado State University
- A complete history of the university, starting from 1870 when it was founded as the Agricultural College of Colorado.
- http://welcome.colostate.edu/index.asp?url=history

The History of Pearl Lake State Park
- Pearl Lake State Park has an exciting history which dates back to the Colorado/Wyoming range wars. Site dedicated to historic preservation and education.
- http://www.pearllakehist.com/

Rocky Mountain National Park History
- D. Ferrel Atkins' brief history of the park.
- http://estes.on-line.com/rmnp/articles/briefhis.html