Ferdinandea is a submerged volcanic island that forms part of the newly discovered underwater volcano Empedocles, 30 km south of Sicily. Currently a seamount, eruptions have raised it above sea level several times before erosion has caused it to submerge again. When it last rose above sea level after erupting in 1831, a four-way dispute over its sovereignty began, which was still unresolved when it disappeared beneath the waves again in early 1832. During its brief life, the French geologist Constant Prévost was on hand, accompanied by an artist, to witness it that July; he named it Île Julia, for its July appearance, and reported in the Bulletin de la Société Géologique de France.
In 2002, renewed seismic activity around Ferdinandea led volcanologists to speculate that a new eruptive episode could be imminent, and the seamount might once more become an island. To forestall a renewal of the sovereignty disputes, Italian divers planted a flag on the top of the volcano in advance of its expected resurfacing. However, the seismicity did not lead to volcanic eruptions and as of 2006 Ferdinandea's summit remains about six meters below sea level.