Poplar River rapids near Lutsen Minnesota

Water cascades over the rocks along the Poplar River that flows through Lutsen Mountains Ski Area in northeastern Minnesota on the north shore of Lake Superior. The Poplar River stretches 21.7 miles (34.9 km) from its source in Gust Lake[3] to its mouth in Lutsen, where it empties into Lake Superior. Its major tributaries are Mistletoe Creek, the Tait River, Caribou Creek, and Barker Creek.[4] It drains an area of 114 square miles (300 km2)[5] lying mostly on the Superior Upland plateau. In its upper reaches, the plateau's slope has an average grade of only 1%, which increases to 4% as the Poplar approaches Superior.[6] Due to the many lakes located in this largely flat watershed, Poplar, along with its neighbors the Temperance, Cross, and Cascade rivers, has a more stable flow and a warmer average water temperature.[7] Three miles from its mouth, the Poplar goes over a series of waterfalls. The 2.2 miles (3.5 km) above the Highway 61 bridge at the mouth of the river are classified as class II-IV+(V) rapids.[8]. Wikipedia