The Sumpter Valley Gold Dredge is a huge piece of mining machinery left in the valley west of Baker City. It chewed through the creek bed in the twentieth century, separating gold from gravel and leaving tailings behind like a man-made moraine.
The dredge is worth the detour because it shows mining at an industrial scale, not the romantic pan-and-pick version. Pair it with the drive through Sumpter and the Elkhorn foothills.