Detroit is the oldest center of civilization in the vast area of the Great Lakes and the Mississippi Valley. Mission and trading posts there were at Chequamegon, Green Bay, Michilimackinac, Chicago, and possibly elsewhere, but all save Detroit were destroyed either temporarily or permanently. The missions at Chequamegon and Chicago were abandoned soon after their establishment, and except for the presence of a few independent traders, the modern settlement of these places dates from the nineteenth century. Michilimackinac, settled earlier than Detroit, still remains a center of civilization; but there have been several removals of the settlement as originally founded, and the present one on the Island dates only from 1780, while the place has steadily dwindled in relative importance from the commercial center of a wide region to a mere summer resort.