Boone spent his final years in Missouri, often in the company of children and grandchildren. He continued to hunt and trap as much as his health and energy levels permitted, intruding upon the territory of the Osage tribe, who once captured him and confiscated his furs. In 1810, at the age of 76, he went with a group on a six-month hunt up the Missouri River, reportedly as far as the Yellowstone River, a round trip of more than 2,000 miles. He began one of his final trapping expeditions in 1815, in the company of a Shawnee and Derry Coburn, a slave who was frequently with Boone in his final years. They reached Fort Osage in 1816, where an officer wrote, "We have been honored by a visit from Col. Boone... He has taken part in all the wars of America, from Braddock's war to the present hour," but "he prefers the woods, where you see him in the dress of the roughest, poorest hunter."