 Blackwater Creek originates on the north slope of Sheep Mesa at an altitude of 11 @,@ 400 feet ( 3 @,@ 500 m ) in Shoshone National Forest and flows north through Blackwater Canyon . The creek is 12 mi ( 19 km ) long and descends a steep gradient before it empties into the North Fork Shoshone River , across from U.S. Routes 14 / 16 / 20 immediately west of Mummy Cave and 15 mi ( 24 km ) east of the border of Yellowstone National Park . The firestorm deaths occurred on the west slopes of Clayton Mountain , approximately 5 mi ( 8 @.@ 0 km ) south by trail into the canyon . The canyon consists of numerous ravines and small ridges , which form a washboard landscape shaped by extensive erosion of the volcanic igneous rock that constitutes the Absaroka Range . The canyon has moderate to steep slopes with a gradient of 20 to 60 percent . The regional flora is an upper montane mixed @-@ conifer forest dominated by Douglas fir trees . When the fire swept through the area the forest was dense and mature with heavy fuel loads from dead trees , which also had dead limbs extending to the ground , providing a fuel ladder for fire to easily spread into the tree tops . 
