Sumpter Valley Gold Dredge
Built in 1935, the last of three built on the Powder River.
The dredge worked a series of buckets into the riverbank and returned the loose rock back onto the dredge for processing. The gold was separated from the sediment using a series of sieves.
By the time it was withdrawn in1954 it is reckoned to have mined more than $4million dollars of gold from the area.