The Big Blow Up was a ” wildfire in the western United States that burned three million acres (4,700 sq mi; 12,100 km2) in North Idaho and Western Montana, with extensions into Eastern Washington and Southeast British Columbia.”
The event galvanized US fire policy with the intent to “never have another fire like this on our watch ever again.”
Accessed September 19th 2019 https://en.wikipedia.org/wiki/Great_Fire_of_1910