A sunken gold dredge on the Inambari River, Peru, about two days travel below the Sandia - San Juan del Oro bridge. The legend is that this dredge was packed into the river by mules in the early part of the 20th century, assembled, and made a fabulous haul of gold the first day of operation. That night, a flood struck and washed the dredge away. True? I don't know, but someone made a huge effort to get some gold out of the river.