big dozers and excavators were put to work to create earthworks to prevent lava flows from getting to the city of Grindavik Iceland

https://www.tumblr.com/armengoldira/740493003808030720/icelandic-earthmovers-outrunning-the-hagafell-lava?source=share

https://www.reddit.com/r/interestingasfuck/comments/196xepi/trying_to_redirect_the_lava_14th_january_2024/

https://www.bloomberg.com/news/articles/2024-01-14/iceland-volcanic-eruption-burns-homes-in-grindavik

On December 27, 1935, the United States Army Air Corps, stationed at the time in Oahu, sent ten bombers to Mauna Loa. 

Twenty 600-pound bombs, containing 300 pounds of TNT-explosive, were dropped on the volcano. 

Geologist E.G. Wingate proposed to "attack the flow channel by dynamiting" and so be more precise and effective in the operation. This didn't happen, as the lava flow stopped six days after the first bomb raid as the summit eruption continued to ease.

Despite the first unsatisfying results, bombs were tried on Mauna Loa a second time in 1942. This time the vents feeding the lava flow were targeted, but again the direct hits were few. Three days after the bombing, the vents partially collapsed by natural processes and caused the main lava flow to stop.

https://www.forbes.com/sites/davidbressan/2022/12/12/when-the-us-army-bombed-mauna-loa-crater-to-turn-aside-a-lava-flow/?sh=469ab5b94d07

https://www.nationalgeographic.com/science/article/why-the-us-once-bombed-an-erupting-volcano
https://www.usgs.gov/news/volcano-watch-did-aerial-bombing-stop-1935-mauna-loa-lava-flow