From last fall when I was at Lassen on a school trip with my daughter's 6th grade class. This is looking down from the top of Cinder Cone. Recent carbon dating and magnetic readings indicate that this eruption of Cinder Cone happened sometime between 1630 and 1670. The main Lassen volcano last blew its top in 1915, and was the last major eruption of the Cascade volcanos until Mt. St. Helens in 1980.