Shield volcanoes are among the largest of volcanoes. They form from layers of lava that flow freely and then harden. The Hawaiian Islands are Shield volcanoes that have formed from a "hot spot" in the Pacific plate of the Crust. As the Pacific plate moves slowly over the "hot spot", lava is released. As time goes by, new Hawaiian Island will form. Mauna Loa is the largest volcano on Earth and is found in Hawaii.