Harsens Island, Michigan

Sans Souci (also Harsens Island) is an unincorporated community in Clay Township of St. Clair County in the U.S. state of Michigan at 42°34′45″N 82°33′51″W / 42.57917°N 82.56417°W / 42.57917; -82.56417 on the eastern shore of Harsens Island. The name is French (sans souci) and can be literally translated to "carefree", "without worries" or "without concerns".

Sans Souci was established as a shipping and trading center on Harsens Island and was given a post office in April 1900. Meaning without care in French, it was named by its first postmaster, William LaCroix, who had large holdings there. The name of the post office was changed to Harsens Island in December 1960.

"Harsens Island" is the name of the post office for the delivery area of ZIP code 48028, which includes the settlement at Sans Souci. "Sans Souci" does not appear in the list of acceptable names for delivery.

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