A significant geological feature of the volcano is the Sciara del Fuoco ( `` Stream of fire '' ) , a big horseshoe-shaped depression generated in the last 13,000 years by several collapses on the northwestern side of the cone .
A significant geological feature of the volcano is the `` Sciara del Fuoco '' ( stream of fire ) , a big horseshoe-shaped depression generated in the last 13,000 years by several collapses on the northwestern side of the cone .