Lake Petenwell is a man-made lake in central Wisconsin, in Adams, Juneau, and Wood counties next to Castle Rock Lake. It covers over 23,000 acres (93 km²) and is 42 feet (13 m) deep. Lake Petenwell is Wisconsin's second largest lake at 23,040 acres (93.2 km²) or approximately 36 square miles (93 km²). It was created in 1948 by the Wisconsin River Power Company with the construction of a dam across the Wisconsin River near Necedah. It has a maximum depth of 42 feet (13 m) and is used for skiing, sailing and fishing. Private lakefront property is very limited as most of the virgin shoreline is undeveloped forest. Wildlife includes wintering bald eagles.