The "Great Explosion" of Lassen Peak 1815 — Eruption column of May 22, 1915 was seen as far as 150 mi (240 km) away. In the foreground is the Loomis Hot Rock, one of the many large boulders dislodged in the eruption that were too hot to touch for days after. (Photograph by B. F. Loomis; modern photo)
Photo Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=44303992