Lac Seul is a large, crescent shaped lake in Kenora District, northwestern Ontario, Canada. It is approximately 241 km (150 mi) long. It has a maximum (regulated) depth of 47.2 m, with a surface elevation of 357 m above sea level. It is the second largest body of water entirely within the province of Ontario (Lake Nipigon being first). The lake consists of open water bays, narrow channels, and islands. It is a relatively shallow lake with many rock shoals. This provides a good habitat for Walleye and Northern pike as well as Bass, Perch, and Muskie.