Mankind's first known attempt to divert a lava flow was in 1669, when a flow from Mount Etna volcano threatened the Sicilian city of Catania. This attempt was largely unsuccessful, in part due to opposition by citizens of another town, Paterno. Attempts to divert lava flows from Mauna Loa Volcano on the island of Hawaii by aerial bombing were made in 1935 and 1942, with no signifcant effects. Earthen bariers were hurriedly constructed in attempts to divert flows from Kilauea Volcano, Hawaii in 1955 and 1960, again with little success.
The first successful lava diversion took place in 1973, when a thick lava flow was impeded and a harbor saved in Iceland by pumping massive quantities of seawater over advancing aa lava. Nonetheless, methods that could be applied to areas far from sources of water remained unproven.
During the 1983 eruption of Etna, Italian scientists managed, for the first time, to convince government authorities that direct intervention in natural volcanic processes was warranted. Both explosives and earthen barriers were used to divert major flows. These efforts were fairly successful, although at the time the historic importance of the operations was not fully recognized.
