In the U.S. state of Arizona, the Boundary Fire (pictured) burned out after 32 days, burning 17,788 acres (7,199 ha) of the Coconino and Kaibab National Forests. Boundary Fire (2017): The Boundary Fire was a 2017 wildfire in Arizona that burned 17,788 acres (7,199 ha) of the Coconino and Kaibab National Forests. The fire was ignited on June 1 when lightning struck a spot on the northeast side of Kendrick Peak within the Coconino National Forest. The fire spread rapidly because of high temperatures, steep terrain, leftover dead trees from a wildfire in 2000, and high wind speeds. July 3, 2017. Wiki link