Born From the Sea
In July 1831 the sea between Sicily and Tunisia boiled with ash and gas. A new island rose from the submarine volcano now known as Empedocles. Reports from Sciacca noted tremors in late June and strong sulfur odors in early July. By mid July an islet with two small lakes stood above the waves.
Claimed By Many
On 17 July 1831 a Sicilian customs official landed and claimed the site for the Kingdom of the Two Sicilies as Ferdinandea. On 2 August Captain Humphrey Fleming Senhouse planted the Union Jack and named it Graham Island for the First Lord of the Admiralty. Spain stated an interest. French geologist Constant Prévost visited and called it Julia after its July birth.
Measurements and Visitors
At its height the island reached about 63 meters above sea level and about 4,800 meters in circumference. Its surface was loose tephra. Tour boats approached. Observers recorded bubbling pools and the two small lakes. Officials and visitors discussed uses that ranged from a naval station to holiday facilities.
Erosion and Disappearance
Wave action eroded the tephra once eruptive activity eased. By December 1831 officials reported retreating shorelines. In January 1832 the island dropped below sea level. The four way dispute ended without resolution as the land sank. Charts later marked a shoal only a few meters below the surface as a hazard to navigation.
Aftershocks and Modern Interest
Fresh activity in 1863 briefly raised the site before it sank again. For decades the summit remained within several meters of the surface. Renewed seismic signals in 2000 and minor gas emissions in 2002 led to monitoring. Italian divers placed a Sicilian flag on the summit in 2000 and later lowered a marble plaque during a ceremony attended by Prince Carlo and Princess Camilla. Within months the plaque fractured underwater.
Science and a Discolored Sun
The 1831 events drew scientists from several countries. Constant Prévost published sketches and notes. Italian and British researchers documented measurements and samples. In August 1831 observers across parts of the world reported a blue or green tinted sun. Early accounts pointed to a distant eruption. Later work rejected some proposed sources and argued that activity at Graham Island was a plausible cause for the atmospheric effect in the regions where it was seen.
A Shoal With A History
Today the site remains a shallow bank in the Strait of Sicily and is sometimes listed on charts as Graham Bank. The feature is part of the larger Empedocles volcanic complex. Mariners track its depth. Local authorities have prepared for any resurfacing to avoid renewed disputes. The island that rose in 1831 remains just under the waves, noted and watched.
In 1831 the sea near Sicily gave birth to an island that amazed sailors and nations alike.
Named and claimed by many, it grew quickly, only to vanish beneath the waves months later—one of several times it has appeared and disappeared in history…🧵👇 pic.twitter.com/OKHSPCDkEH
— Fascinating True Stories (@FascinatingTrue) September 16, 2025