Lake Winnebago itself is the largest inland body of water in the state of Wisconsin. Lake Winnebago is 137,708 acres with a maximum depth of 21 feet and an average depth of 7 feet. It is approximately 30 miles long and 10 miles wide.
The Lake Winnebago System is one of the nations top Walleye fisheries. Lakes Butte des Morts, Winneconne and Poygan are known as the Upriver Lakes and are attached by the Fox and Wolf rivers.