Heirisson Island

The oddity, explained

Why is Heirisson Island unusual?

Heirisson Island appears here because the approved source classifies it as infrastructure. The source describes it as chain of islands in Swan River, Western Australia, later filled to make one. Heritage Atlas treats that specific classification-and-description combination as the oddity; the score is a comparative discovery signal, not proof of mystery or the supernatural.

Evidence and further exploration

The coordinate, category and description remain tied to the cited source. Comparative oddness helps discovery; it does not add facts that the source does not provide.