For centuries, the Tidewater coast of North Carolina has held one of early America’s oldest secrets: the fate of more than 100 English colonists who vanished from their island outpost in the late 1500s.

Theories abound about what happened to the so-called Lost Colony, ranging from sober scholarship to science fiction. Some historians believe that the colonists might have been absorbed into American Indian tribes. Other explanations point to darker fates, like disease, an attack by Spaniards or violence at the hands of Indians. The wild-eyed fringe hints at cannibalism and even alien abduction.

The shroud of mystery may finally be lifting. The British Museum’s re-examination of a 16th-century coastal map using 21st-century imaging techniques has revealed hidden markings that show an inland fort where the colonists could have resettled after abandoning the coast.

The findings, announced Thursday morning, bring into focus a puzzle that has long fed the feverish curiosity of historians, archaeologists and amateur sleuths. Folklore has flourished over the colonists’ fate, including that of the first child of English descent born in the Americas, Virginia Dare.