Tank Cottage: Wisconsin's Oldest Building

Inside Heritage Hill State Historical Park, surrounded by modern Green Bay, stands a low French-Canadian log structure that may be the oldest building in the entire state of Wisconsin. The Tank Cottage was built by Joseph Roi, a French-Canadian fur trader, somewhere between seventeen seventy-six and eighteen oh three. He used a traditional Quebec construction technique called pièce-sur-pièce à coulisse, hewn logs slotted vertically into grooved posts, each course stacked tightly against the next.

The result was a snug, durable building that has survived more than two centuries. Roi used the cottage as a residence and trading post near the Fox River. In eighteen oh five he sold it to Jacques Porlier, who aligned with the British during the War of eighteen twelve and briefly made the building a local British headquarters.

In eighteen fifty, a Norwegian Moravian missionary named Nils Otto Tank purchased the structure along with a large tract of Fox River land, and gave the cottage the name it carries today. The Library of Congress documented the building through its Historic American Buildings Survey. It was listed on the National Register of Historic Places in nineteen seventy and relocated in nineteen seventy-six to Heritage Hill, where it serves as a museum within a fifty-six-acre living history park that spans four centuries of northeastern Wisconsin history.

Hazelwood, the Greek Revival home of lawyer and Wisconsin constitution-drafter Morgan Lewis Martin, built in eighteen thirty-seven, stands nearby, making Heritage Hill something of a compressed archive of Green Bay's founding generations.