On their return trip from the Pacific Coast, the Corps of Discovery split into two parties at Travelers Rest, just south of Missoula, Montana, on July 1, 1806. Clark proceeded south along the route they had followed in 1805 beside the Bitterroot River, while Lewis went north along the Blackfoot River, planning to rendezvous at the Missouri River in late August. Lewis traveled through this area with nine mounted soldiers, 17 horses, and his Newfoundland dog, Seaman. On July 5, 1806, they camped near the confluence of the Big Blackfoot River and a creek that Lewis named Seaman's Creek after his dog; today it is called Monture Creek after George Monture, an early U.S. Army scout. Lewis called this part of the valley a "prarie of the knobs" because of the mounds along the trail, some of which still remain. The Nez Perce knew the trail as "COKALAHJSHKHT," or "The River of the Road to the Buffalo." From here the party continued east past Lincoln, up Alice Creek, and across the Continental Divide at the place now known as Lewis and Clark Pass, although Clark was never there. The knobs Lewis observed were formed by glaciers dropping rocks along their edges and into icy holes and cracks, and the glaciers that left them began melting and slowly retreating north about 10,000 to 12,000 years ago.