Door County: Limestone, Cherries, and the Door of the Dead

The Door Peninsula juts northeast from the Wisconsin mainland like a narrow thumb pointing into Lake Michigan, dividing the main body of the lake from Green Bay to the west. It is barely ten miles across in places, with cold open water on both sides and limestone bedrock just beneath the surface. At its northern tip a two-mile strait of unpredictable currents and shallow shoals connects Lake Michigan to Green Bay.

French voyageurs called that passage Porte des Morts, the Door of the Dead, and from that name came everything else: Door County, the county seat of Sturgeon Bay, the identity of the whole peninsula. The limestone is not incidental. Ancient coral reefs built up the Niagaran dolomite that underlies this land four hundred million years ago, when this part of North America lay under a warm shallow sea.

That stone now forms the Niagara Escarpment, a ridge that defines the eastern edge of the peninsula and creates the bluffs that drop forty and fifty and a hundred feet to the water at places like Eagle Bluff and Ellison Bay and the northern tip. The thin soil above the limestone and the moderating influence of two large lakes create a climate unlike anywhere else in the upper Midwest: cool springs, mild summers, and long autumns that allow tart cherries to ripen without the late frosts that would kill the blossoms further inland. Door County became one of the most important cherry growing regions in the United States, though Michigan is now the nation's leading tart cherry producer.

The Potawatomi were here when French traders arrived in the sixteen hundreds. Moravian settlers from Norway walked to Eagle Harbor over the ice in eighteen fifty-three and founded the village of Ephraim. Scandinavian fishermen came in the eighteen sixties and seventies, finding the cold water and rocky shores not unlike home.

Norwegian settlers brought skills and names and faces that persist in this peninsula to the present generation. More than two million visitors come each year for the lighthouses and state parks and cherry orchards and fish boils and the simple fact that the water is always visible and the air smells like the lake. The Door of the Dead turned out to be the door to one of the most visited places in the Midwest.