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On a Polish island, a wood-carved face may have ancient spiritual significance. In the Bahamas, discoveries from a sunken treasure ship reveal the cause of the disaster. At San Teodoro Cave, evidence shows humans reached a nearby island later than expected, and North Sentinel Island remains isolated and fiercely protected from the modern world.

Off Ireland’s coast, maps marked the phantom island Hy-Brasil for centuries, but was it lost or an illusion? In Argentina, a perfectly circular island called “The Eye” rotates within a ring-shaped lake. In Madagascar, the vast cliffside complex of Teniky hints at a lost past. On Pantelleria, hidden Roman coins capture a moment frozen in time

In Budapest, beneath the ruins of a medieval monastery on Margaret Island, archaeologists uncover the victim of a medieval killing — his identity lost, and his death shrouded in secrecy — but what led to this violent end? In Italy’s Venetian Lagoon, the shifting sandbar Bacan has suddenly stabilized, defying its natural cycle and raising new questions about the forces reshaping it. On Denmark’s Als, a buried boat surrounded by weapons hints at a forgotten conflict. Was it lost in battle or offered in ritual? And on Ethiopia’s Daga Island, mummified emperors lie hidden within a monastery, their presence tied to power, faith and enduring legend.

The ruins of a mysterious castle on a New York island reveal a hidden arsenal tied to one of America’s largest weapons empires.