What island did early American settlers simply disappear from?

Hi.Sorry if this sounds very vague. I remember reading about an island (or possible coastal town) that was settled by early Americans. Houses were built and a community was raised,etc. But years later,it was found abandoned with no clue as to where the settlers went. What was the name of this island or coastal town? And has it ever been established to where these people went to and why? Thanks. X Sarah