We utilized 10 years of fire data from the Colorado Fire Project, in connection with several GIS databases, to illustrate a method of assigning large-wildfire risk indices to the watersheds of the mountainous western side of Colorado. This was done to identify high-risk areas so that other working groups could utilize wildfire locations, sizes, probabilities, and probable effects as a basis for indexing the risks posed to environmental and cultural resources in the State. The basic questions were: (1) where are large wildfires most likely to be experienced in the future, and (2) what kinds of effects might such fires cause?