The East Troublesome fire is a wildfire in the Rocky Mountains west of Rocky Mountain National Park in Grand County, Colorado, United States. The fire started on Wednesday October 14th, 2020 at approx. 04:00 PM, near East Troublesome Creek, and the cause is still unknown. On October 22, it became the 4th largest recorded wildfire in Colorado's history at around 125,000 acres, exploding from around 40,000 acres the day prior.