FORT BOONESBOROUGH, Ky. — Keeping up a quick pace to the finish line, Curtis Penix didn’t look like someone who had walked nearly 240 miles in the footsteps of frontiersman Daniel Boone, an arduous trip through the Appalachian terrain that was inspired by his own family’s pioneering roots in the Kentucky wilderness. The Michigan steel mill worker, toting a 40-pound backpack, completed his 16-day journey Thursday.