To avoid the series of waterfalls along the Missouri River north of this point, the Lewis and Clark Expedition portaged their canoes and several tons of baggage, crossing the route here. At the lower camp, some 12 miles northeast, the crew made crude wagons with wheels sliced off a cottonwood tree. The upper camp, named after the bears that inhabited the islands, was located some 5 miles southwest. The portage was near man-killing, and the men had to haul with all their strength, Clark wrote.