Global Volcanism Program | Image GVP-09136
An eruption plume above the summit crater of Irazú is seen here in 1917 from the national theater in San José. All summit craters were reported to be smoking on September 27, 1917, after which activity steadily intensified. Ash fell in Curridabat on November 18, and again a month later, when ash also fell in Tres Ríos. On January 6, 1918 ashfall reached San José, Heredia and Puriscal. Intermittent explosive activity continued until 1921, with the most violent event occurring on November 30, 1918, when ash reached as far as Nicoya.
Anonymous, 1917 (published in Alvarado, 1989).