The lost colony of Roanoke
This is one of the more spooky ones. Back in 1587, John White founded an English colony on Roanoke Island in North Carolina. He left the colony shortly after for more supplies. Three years later, he returned, only to find the colony meticulously abandoned with all the homes and fortifications dismantled. There was no sign or clue of where his people had gone, other than the word “Croatoan” carved into a tree.
Whether the colonists were slain by the local natives, or wandered away into the wilderness, no one knows. There was never any archeological or historical sign of the people ever again.
Like I said, spooky.