Before Waldo Canyon, Black Forest and Marshall, the Fourmile Canyon Fire was Colorado’s most destructive.
Igniting September 6, 2010 west of Boulder from an improperly extinguished residential fire pit that reignited in the wind, the fire burned 6,181 acres and destroyed 169 homes, the most destructive and, at roughly $217 million in insured losses, the costliest wildfire in state history at the time.
Every major Colorado fire reinforces the same lesson: the homes most likely to survive are the ones prepared before a fire starts. An everyday backyard fire pit caused it, a reminder that ignition prevention and the noncombustible zone around a home matter enormously. Creating defensible space, hardening the home against embers, and documenting the work for insurance and grant funding are the highest-leverage steps a homeowner can take.
Homeowners in the Fourmile Canyon footprint can get a free assessment from our Boulder County and Boulder teams.
Not sure where your property stands? Check your wildfire risk score in under a minute, watch for new starts on the active fires map, and set up emergency fire alerts so you never miss an evacuation order.
The CalWood Fire (2020) burned 10,113 acres near Jamestown in Boulder County and destroyed 26 homes. Cause, size and aftermath.
Read the overviewThe NCAR Fire (2022) burned 190 acres near Boulder but destroyed no homes, a widely cited wildfire mitigation success. What worked and why.
Read the overviewThe Black Tiger Fire (1989) burned 2,100 acres in Boulder County's Sugarloaf area and destroyed 39 homes, a landmark national wildland-urban interface case study.
Read the overviewThe complete, searchable record of every major Colorado wildfire in history.
Open the full guide169 homes, the most destructive in Colorado at the time.
An improperly extinguished residential fire pit that reignited.
