Mounting a hill near Black Eagle Falls (probably where the town of Black Eagle is today), Lewis saw that the cataracts ended and that another large river joined the Missouri about two and a half miles further upstream. Although it was very late in the afternoon, Lewis rushed forward to see this river and was attacked by a grizzly bear. He ran more than 80 yards and launched himself into the Missouri River, and luckily the bear did not follow. The Lewis and Clark Expedition was forced to portage around the Great Falls, an arduous task that took nearly a month.