An explanation with the photo says that it is one of the two Italian-built Sisu class boats – Sisu or Hurja. The vessels were constructed in 1917 by the Orlando shipyard in Livorno, Italy. Sisu and Hurja were purchased by the Finns in 1922, and saw service in World War II. As can be seen form the photo, when dashing forward at full speed, the vessels sprayed water high in the air, earning the nickname “the fountains” from Finnish sailors.